Question
A group of workers was put on a job. From the second
day onwards, 1 worker left work everyday. If no worker was left when 52% of the work gets completed, find the number of workers in the group initially?Solution
Let x men doing a work and from second day onwards 1 worker left work, then wok will be completed in x days. x + x – 1 + x – 2 + ……….. x – n = x men Sum of n numbers(Sn) = n/2 [2a + (n -1)d] ⇒ x/2 [2 x + (x -1)(-1)] ⇒ x/2 [2 x – x + 1] ⇒ x/2 [x + 1] If no one would leave the work then, x/2 [x + 1] = x × x ×  52/100 ⇒ x + 1 = 52x/50 ⇒ 50x + 50 = 52 x ∴x = 25
Find the wrong number in the given number series.
77, 101, 139, 197, 281, 413
8Â Â Â Â Â 5Â Â Â Â Â Â 6.5Â Â Â Â Â 11.75Â Â Â Â Â 26Â Â Â Â Â 65
...Find the wrong number in the given number series.
263, 133, 201, 505, 1771, 7974
- Find the wrong number in the given number series.
10, 19, 3, 28, 5, 54 121Â Â Â Â Â 127Â Â Â Â Â Â 133Â Â Â Â Â Â 142Â Â Â Â Â Â 160Â Â Â Â Â Â 206
...8 10.4 6.8 10.2 7.6 10
- Find the wrong number in the given number series.
5, 10, 20, 35, 80, 160 60, 63, 71, 86, 125, 145
- Find the wrong number in the given number series.
300, 600, 200, 900, 112.5, 1125 - Find the wrong number in the given number series.
1, 2, 6, 24, 120, 600
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