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उत्तर : 4. "E = 4 & Y = 2"
व्याख्या :

Answer: D) E = 4 & Y = 2 Explanation: Let the the age of the elder boy = E   Let the the age of the younger boy = Y   Given that Y = cube root of EY   => Y3 = EY => E = Y2 .....(1)By the condition of number replacement the age of the father is YE   The Mother's age = EY/2   But she is 3 years less than father => EY/2 + 3 = YE2YE = EY + 6 ......(2)   Then now from the given options we can identify which satisfies the all the conditions.   Here Y =2 and E = 4 satisfies all the conditions.

प्र: Equal quantities of three mixtures of milk and water are mixed in the ratio 1:2, 2:3 and 3:4. The ratio of water and milk in the mixture is ? 3259 0

  • 1
    193 : 122
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  • 2
    97 : 102
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  • 3
    115 : 201
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  • 4
    147 : 185
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    गलत
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उत्तर : 1. "193 : 122"
व्याख्या :

Answer: A) 193 : 122 Explanation: Given the three mixtures ratio as (1:2),(2:3),(3:4) (1+2),(2+3),(3+4) Total content = 3,5,7   Given equal quantities of the three mixtures are mixed, then LCM of 3, 5, 7 = 105 105/3 = 35 , 105/5 = 21 , 105/7 = 15   Now, the individual equal quantity ratios are (35x1, 35x2), (21x2, 21x3), (15x3, 15x4)  i.e (35,70), (42,63), (45,60)   So overall mixture ratio of milk and water is 35+42+45 : 70+63+60 122:193   But in the question asked the ratio of water to milk = 193 : 122

प्र: A man has only 20-paise and 25-paise coins in a bag. If he has 50 coins in all totaling to Rs.10.25, then the number of 20-paise coins is 1121 0

  • 1
    42
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  • 2
    45
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  • 3
    38
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  • 4
    36
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उत्तर : 2. "45"
व्याख्या :

Answer: B) 45 Explanation: Let number of 20 ps coins = x and number of 25 ps coins = y Given total coins in the bag = 50 x + y = 50.......(1) But the total money in the bag = Rs. 10.25 0.20x + 0.25y = 10.25 20x + 25y = 1025.........(2) Now multiplying (1) by 25 we get 25x+25y=1250.............(3) By solving (2) and (3) 20x + 25y = 1025; => x = 45; Then, the no. of 20 ps coins are 45.

प्र: The sum of 3rd and 15th elements of an arithmetic progression is equal to the sum of 6th, 11th and 13th elements of the same progression. Then which element of the series should necessarily be equal to zero ? 2503 1

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    14th element
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  • 2
    9th element
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  • 3
    12th element
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  • 4
    7th element
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उत्तर : 3. "12th element"
व्याख्या :

Answer: C) 12th element Explanation: If we consider the third term to be ‘x”The 15th term will be (x + 12d)6th term will be (x + 3d)11th term will be (x + 8d) and 13th term will be (x + 10d).Thus, as per the given condition, 2x + 12d = 3x + 21d.Or x + 9d = 0.x + 9d will be the 12th term. Thus, 12th term of the A.P will be zero.

प्र: If 4th december 1999 is Monday then what day is 3rd january 2000 ? 2874 0

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    Sunday
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  • 2
    Monday
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  • 3
    Tuesday
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  • 4
    Wednesday
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उत्तर : 4. "Wednesday"
व्याख्या :

Answer: D) Wednesday Explanation: Here from 4th December 1999 to 3rd January 2000,there is a difference of 30 days.Number of odd days = 30/7 = 2 odd days Then no. of odd days = 2 => tuesday and wednesday(from monday). Hence on 3rd january it is wednesday.

प्र: 20 men went to a restaurant. Ninteen of them paid Rs.70 each and the twentieth man paid Rs.90.25 more than the average of all the 20 men. What is the total bill ? 1920 0

  • 1
    Rs. 1495
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  • 2
    Rs. 548
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  • 3
    Rs. 850
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  • 4
    Rs. 1750
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उत्तर : 1. "Rs. 1495"
व्याख्या :

Answer: A) Rs. 1495 Explanation: Let the average bill paid by twenty members = 'x' But 19 men paid each = Rs. 70 20th man paid Rs. 90.25 more than the avg bill of 20 = x + 90.25 20x = 19(70) + x + 90.2519x = 1330 + 90.2519x = 1420.25x = 1420.25/19 = Rs. 74.75 But the total bill = 20 x 74.75 = Rs. 1495.

प्र: What is the next number in series? 10, 9, 60, 90, 70, 66, ? 2161 0

  • 1
    73
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  • 2
    19
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  • 3
    96
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  • 4
    22
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उत्तर : 3. "96"
व्याख्या :

Answer: C) 96 Explanation: ten = 3(number of letters)nine = 4(number of letters)sixty = 5(number of letters)ninety = 6(number of letters)seventy = 7(number of letters)sixtysix = 8(number of letters)ninetysix=96(number of letters) Then, likwise choose the number which has 9 letters in its Spelling.

प्र: From the given series of numbers, if half of the second highest number is subtracted from the third highest number, what will be the value ? 519 328 746 495 837 1684 0

  • 1
    146
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  • 2
    203
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  • 3
    345
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  • 4
    96
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उत्तर : 1. "146"
व्याख्या :

Answer: A) 146 Explanation: From the given series of numbers, if half of the second highest number is subtracted from the third highest number, what will be the value ? Now arranging the given numbers in descending order.837 746 519 495 328 519 - 746/2 = 519 - 373 = 146.

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