The average of 15 numbers is 18. The average of first 8 is 19 and that last 8 is 17, then the 8th number is
(A) 15
(B) 16
(C) 18
(D) 20
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A number x is selected at random from the numbers 1, 2, 3 and 4. Another number y is selected at random from the numbers 1, 4, 9 and 16.
x can be any one of 1, 2, 3 or 4. y can be any one of 1, 4, 9 or 16 Total number of cases of product of x and y...
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The sum of four consecutive numbers in an AP is 32 and the ratio of the product of the first and the last term to the product of the middle terms
Let the four consecutive numbers in AP be (a - 3d), (a - d), (a + d) and (a + 3d) So, according to the question. a-3d + a - d +...
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The average of five numbers is 281. The average of the first two numbers is 280 and the average of the last two numbers is 178.5.
(a) Assume the third number = x According to question 2 × 280 + x + 178.5 × 2 = 281 × 5 or, 560 + x + 357 = 1405 or, x +...
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The sum of five numbers is 290. The average of the first two numbers is 48.5 and the average of last two numbers is 53.5.
(e) Third number = 290 – (48.5 × 2) – (53.5 × 2) = 290 – 97 – 107= 86
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The average of 5 positive integers is 436. The average of the first two numbers is 344 and the average
(d) Third number = (436 × 5) – (344 × 2 + 554 × 2) = 2180 – 1796 = 384
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The numbers 13 and 31 are prime numbers. Both these numbers have same digits 1 and 3.Find such pairs of prime numbers up to 100.
17 and 71; 37 and 73; 79 and 97
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Between which two whole numbers on the number line are the given lie? Which of these whole numbers is nearer the number?
(a) From 0 to 1, 0.8 is nearest to 1. (b) From 5 to 6, 5.1 is nearest to 5. (c) From 2 to 3, 2.6 is nearest to 3. (d) From 6...
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A number with three or more digits is divisible by 6, if the number formed by its last two digits (i.e., ones and tens) is divisible by 6.
A number with three or more digits is divisible by 6, if the number formed by its last two digits (i.e., ones and tens) is divisible by 6. False
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If the HCF of two numbers is one of the numbers, then their LCM is the other number.
If the HCF of two numbers is one of the numbers, then their LCM is the other number. True
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A mobile number consists of ten digits. The first four digits of the number are 9, 9, 8 and 7. The last three digits are 3, 5 and 5.
These digits are 6, 4, 2.
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