Examsbook | Hand picked material and question banks

प्र: 10 boys can complete a work in 7 days and 10 girls take 14 days to complete the work. How many days will 5 boys and 10 girls take to complete the work ? 1254 0

उत्तर : 3. "7 days"
व्याख्या :
Answer: C) 7 days Explanation: 1 boy's 1 day work = 1/70 1 girl's 1 day work = 1/140 (5 boys + 10 girls)'s 1 day work = (5/70 + 10/140) = (1/14 + 1/14) = 1/7 5 boys and 10 girls will complete the work in 7 days.

प्र: The circumferences of two circles are 264 meters and 352 meters. Find the difference between the areas of the larger and the smaller circles ? 3117 0

उत्तर : 3. "4312 sq.m"
व्याख्या :
Answer: C) 4312 sq.m Explanation: Let the radii of the smaller and the larger circles be 's' m and 'l' m respectively. 2πs = 264 and 2πl = 352 s = 2642π and l = 3522π Difference between the areas =πl2-πs2 = π1762π2-1322π2 = 1762π-1322π = (176 - 132)(176 + 132) / π = (44 x 308) / (22/7) = 4312 sq.m

प्र: The compound interest earned by Sunil on a certain amount at the end of two years at the rate of 8% p.a. was Rs.2828.80. Find the total amount that Sunil got back at the end of two years in the form of principal plus interest earned ? 2175 0

उत्तर : 2. "Rs. 19828.80"
व्याख्या :
Answer: B) Rs. 19828.80 Explanation: Let the sum be Rs. P P{ 1+81002- 1 } = 2828.80 It is in the form of a2-b2 = a+ba-b P(8/100)(2 + 8/100) = 2828.80 P = 2828.80 / (0.08)(2.08) = 1360/0.08 = 17000 Principal + Interest = Rs. 19828.80

प्र: Rifath Sharook has designed the world’s lightest satellite “KalamSat”. He hails from which country ? 1271 0

उत्तर : 4. "India"
व्याख्या :
Answer: D) India Explanation: Indian teen Rifath Sharook from Tamil Nadu has designed the world’s lightest & smallest satellite named “KalamSat”. The satellite weighs only 64 grams and will be launched by NASA on June 21, 2017. With this, he will become the first Indian student to have his experiment launched by NASA. The main role of the satellite will be to demonstrate the performance of 3-D printed carbon fibre. The satellite has been designed in a way which will have a 240-minute mission in space and will operate for 12 minutes in a micro-gravity environment of space.

प्र: There are 100 students in 3 sections A, B and C of a class. The average marks of all the three sections was 84. The average of B and C was 87.5 and the average marks of students in A section was : 4167 0

उत्तर : 1. "20"
व्याख्या :
Answer: A) 20 Explanation: Numbers of students in section A = x ∴ Numbers of students in section B and C = (100 – x) ∴ x 70 + (100 – x) 87.5 = 84 100 => 70x + 87.5 100 – 87.5x = 8400 => 8750 – 17.5x = 8400 => 17.5x = 8750 – 8400 => x = 20.

प्र: A jogger running at 9 kmph alongside a railway track is 240 metres ahead of the engine of a 120 metre long train running at 45 kmph in the same direction. In how much time will the train pass the jogger ? 1664 0

उत्तर : 3. "36 sec"
व्याख्या :
Answer: C) 36 sec Explanation: Given speed of jogger = 9 kmph Speed of train = 45 kmphAs they are in same direction, Relative speed = 45 - 9 = 36 kmph = 36x5/18 = 10 m/sDistance = 240 + 120 = 360 mts Time = distance/speed = 360/10 = 36 sec.

प्र: The arithmetic mean of the following numbers 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6 and 7, 7, 7, 7, 7, 7, 7 is ? 2265 0

उत्तर : 4. "5"
व्याख्या :
Answer: D) 5 Explanation: Arithmatic mean = sum/members => (1x1 + 2x2 + 3x3 + 4x4 + 5x5 + 6x6 + 7x7) / (1 + 2 + 3 + 4 + 5 + 6 + 7) => 140/28 = 5

प्र: The two trains of lengths 400 m, 600 m respectively, running at same directions. The faster train can cross the slower train in 180 sec, the speed of the slower train is 48 kmph. Then find the speed of faster train ? 3990 0

उत्तर : 1. "68 kmph"
व्याख्या :
Answer: A) 68 kmph Explanation: Let the speed of the faster train be 'X' kmph, Then their relative speed= X - 48 kmphTo cross slower train by faster train, Distance need to be cover = (400 + 600)m = 1 km. and Time required = 180 sec = 180/3600 hr = 1/20 hr.Time = Distance/Speed => 1/20 = 1/(x-48)X = 68 kmph

प्र: 10 boys can complete a work in 7 days and 10 girls take 14 days to complete the work. How many days will 5 boys and 10 girls take to complete the work ? 1254 0

उत्तर : 3. "7 days"
व्याख्या :
Answer: C) 7 days Explanation: 1 boy's 1 day work = 1/70 1 girl's 1 day work = 1/140 (5 boys + 10 girls)'s 1 day work = (5/70 + 10/140) = (1/14 + 1/14) = 1/7 5 boys and 10 girls will complete the work in 7 days.

प्र: The circumferences of two circles are 264 meters and 352 meters. Find the difference between the areas of the larger and the smaller circles ? 3117 0

प्र: The compound interest earned by Sunil on a certain amount at the end of two years at the rate of 8% p.a. was Rs.2828.80. Find the total amount that Sunil got back at the end of two years in the form of principal plus interest earned ? 2175 0

उत्तर : 2. "Rs. 19828.80"
व्याख्या :
Answer: B) Rs. 19828.80 Explanation: Let the sum be Rs. P P{ 1+81002- 1 } = 2828.80 It is in the form of a2-b2 = a+ba-b P(8/100)(2 + 8/100) = 2828.80 P = 2828.80 / (0.08)(2.08) = 1360/0.08 = 17000 Principal + Interest = Rs. 19828.80

प्र: Rifath Sharook has designed the world’s lightest satellite “KalamSat”. He hails from which country ? 1271 0

प्र: There are 100 students in 3 sections A, B and C of a class. The average marks of all the three sections was 84. The average of B and C was 87.5 and the average marks of students in A section was : 4167 0

प्र: A jogger running at 9 kmph alongside a railway track is 240 metres ahead of the engine of a 120 metre long train running at 45 kmph in the same direction. In how much time will the train pass the jogger ? 1664 0

उत्तर : 3. "36 sec"
व्याख्या :
Answer: C) 36 sec Explanation: Given speed of jogger = 9 kmph Speed of train = 45 kmphAs they are in same direction, Relative speed = 45 - 9 = 36 kmph = 36x5/18 = 10 m/sDistance = 240 + 120 = 360 mts Time = distance/speed = 360/10 = 36 sec.

प्र: The arithmetic mean of the following numbers 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6 and 7, 7, 7, 7, 7, 7, 7 is ? 2265 0

उत्तर : 4. "5"
व्याख्या :
Answer: D) 5 Explanation: Arithmatic mean = sum/members => (1x1 + 2x2 + 3x3 + 4x4 + 5x5 + 6x6 + 7x7) / (1 + 2 + 3 + 4 + 5 + 6 + 7) => 140/28 = 5

प्र: The two trains of lengths 400 m, 600 m respectively, running at same directions. The faster train can cross the slower train in 180 sec, the speed of the slower train is 48 kmph. Then find the speed of faster train ? 3990 0

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

प्र: 10 boys can complete a work in 7 days and 10 girls take 14 days to complete the work. How many days will 5 boys and 10 girls take to complete the work ? 1254 05b5cc6dee4d2b4197774ea85

उत्तर : 3. "7 days" व्याख्या :Answer: C) 7 days Explanation: 1 boy's 1 day work = 1/70 1 girl's 1 day work = 1/140 (5 boys + 10 girls)'s 1 day work = (5/70 + 10/140) = (1/14 + 1/14) = 1/7 5 boys and 10 girls will complete the work in 7 days.

प्र: The circumferences of two circles are 264 meters and 352 meters. Find the difference between the areas of the larger and the smaller circles ? 3117 05b5cc6dee4d2b4197774ea79

प्र: The compound interest earned by Sunil on a certain amount at the end of two years at the rate of 8% p.a. was Rs.2828.80. Find the total amount that Sunil got back at the end of two years in the form of principal plus interest earned ? 2175 05b5cc6dee4d2b4197774ea74

उत्तर : 2. "Rs. 19828.80" व्याख्या :Answer: B) Rs. 19828.80 Explanation: Let the sum be Rs. P P{ 1+81002- 1 } = 2828.80 It is in the form of a2-b2 = a+ba-b P(8/100)(2 + 8/100) = 2828.80 P = 2828.80 / (0.08)(2.08) = 1360/0.08 = 17000 Principal + Interest = Rs. 19828.80

प्र: Rifath Sharook has designed the world’s lightest satellite “KalamSat”. He hails from which country ? 1271 05b5cc6dee4d2b4197774ea6f

प्र: There are 100 students in 3 sections A, B and C of a class. The average marks of all the three sections was 84. The average of B and C was 87.5 and the average marks of students in A section was : 4167 05b5cc6dee4d2b4197774ea65

प्र: A jogger running at 9 kmph alongside a railway track is 240 metres ahead of the engine of a 120 metre long train running at 45 kmph in the same direction. In how much time will the train pass the jogger ? 1664 05b5cc6dee4d2b4197774ea5b

उत्तर : 3. "36 sec" व्याख्या :Answer: C) 36 sec Explanation: Given speed of jogger = 9 kmph Speed of train = 45 kmphAs they are in same direction, Relative speed = 45 - 9 = 36 kmph = 36x5/18 = 10 m/sDistance = 240 + 120 = 360 mts Time = distance/speed = 360/10 = 36 sec.

प्र: The arithmetic mean of the following numbers 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6 and 7, 7, 7, 7, 7, 7, 7 is ? 2265 05b5cc6dee4d2b4197774ea60

उत्तर : 4. "5" व्याख्या :Answer: D) 5 Explanation: Arithmatic mean = sum/members => (1x1 + 2x2 + 3x3 + 4x4 + 5x5 + 6x6 + 7x7) / (1 + 2 + 3 + 4 + 5 + 6 + 7) => 140/28 = 5

प्र: The two trains of lengths 400 m, 600 m respectively, running at same directions. The faster train can cross the slower train in 180 sec, the speed of the slower train is 48 kmph. Then find the speed of faster train ? 3990 05b5cc6dee4d2b4197774ea56

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

त्रुटि की रिपोर्ट करें

प्र: 10 boys can complete a work in 7 days and 10 girls take 14 days to complete the work. How many days will 5 boys and 10 girls take to complete the work ? 1254 0

उत्तर : 3. "7 days"
व्याख्या :
Answer: C) 7 days Explanation: 1 boy's 1 day work = 1/70 1 girl's 1 day work = 1/140 (5 boys + 10 girls)'s 1 day work = (5/70 + 10/140) = (1/14 + 1/14) = 1/7 5 boys and 10 girls will complete the work in 7 days.

प्र: The circumferences of two circles are 264 meters and 352 meters. Find the difference between the areas of the larger and the smaller circles ? 3117 0

प्र: The compound interest earned by Sunil on a certain amount at the end of two years at the rate of 8% p.a. was Rs.2828.80. Find the total amount that Sunil got back at the end of two years in the form of principal plus interest earned ? 2175 0

उत्तर : 2. "Rs. 19828.80"
व्याख्या :
Answer: B) Rs. 19828.80 Explanation: Let the sum be Rs. P P{ 1+81002- 1 } = 2828.80 It is in the form of a2-b2 = a+ba-b P(8/100)(2 + 8/100) = 2828.80 P = 2828.80 / (0.08)(2.08) = 1360/0.08 = 17000 Principal + Interest = Rs. 19828.80

प्र: Rifath Sharook has designed the world’s lightest satellite “KalamSat”. He hails from which country ? 1271 0

प्र: There are 100 students in 3 sections A, B and C of a class. The average marks of all the three sections was 84. The average of B and C was 87.5 and the average marks of students in A section was : 4167 0

प्र: A jogger running at 9 kmph alongside a railway track is 240 metres ahead of the engine of a 120 metre long train running at 45 kmph in the same direction. In how much time will the train pass the jogger ? 1664 0

उत्तर : 3. "36 sec"
व्याख्या :
Answer: C) 36 sec Explanation: Given speed of jogger = 9 kmph Speed of train = 45 kmphAs they are in same direction, Relative speed = 45 - 9 = 36 kmph = 36x5/18 = 10 m/sDistance = 240 + 120 = 360 mts Time = distance/speed = 360/10 = 36 sec.

प्र: The arithmetic mean of the following numbers 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6 and 7, 7, 7, 7, 7, 7, 7 is ? 2265 0

उत्तर : 4. "5"
व्याख्या :
Answer: D) 5 Explanation: Arithmatic mean = sum/members => (1x1 + 2x2 + 3x3 + 4x4 + 5x5 + 6x6 + 7x7) / (1 + 2 + 3 + 4 + 5 + 6 + 7) => 140/28 = 5

प्र: The two trains of lengths 400 m, 600 m respectively, running at same directions. The faster train can cross the slower train in 180 sec, the speed of the slower train is 48 kmph. Then find the speed of faster train ? 3990 0