Question
How many numbers in the range from 150 to 1000 are
divisible by 5, 10, and 20?Solution
ATQ;
If a number is a multiple of 5, 10, and 20, then the number is a multiple of the L.C.M of 5, 10, and 20.
L.C.M of 5, 10, and 20 = 20
Smallest multiple of 20 between 150 and 1000 = 160
Largest multiple of 20 between 150 and 1000 = 1000
Common difference = 20
Let the required number of terms be 'n'.
So, 160 + (n - 1) × 20 = 1000
Or, n - 1 = (1000 - 160) ÷ 20 = 42
So, n = 42 + 1 = 43
So, there are 43 numbers between 150 and 1000 which are multiples of 5, 10, and 20.
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A series is given with one wrong term. Select the correct alternative from the given ones that will complete the series.
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8, 20, 48, 108, 232, 482
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Find the wrong number in the series given below.
6, 19, 59, 182, 544, 1637
Find the wrong number in the series given below.
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In the following question, select the wrong number from the given alternatives.
43, 50, 64, 85, 113, 138
A series is given with two wrong terms. Select the wrong term in the given series.
32, 43, 58, 73, 92, 117, 144
