Question
A student multiplied a number by 4/5 instead of 5/4.
What is the percentage error in the calculation.Solution
Let the required number = (LCM of denominator 4 and 5) = 20 According to the question, Wrong answer = 4/5  × 20 = 16 Correct answer = 5/4  × 20 = 25 Required percentage of error =  (25-16)/25  × 100 = 36%
169, 224, 293, 385, 497, 629
Find the wrong number in the given number series.
20, 33, 50, 69, 93, 121
25Â Â Â 26Â Â Â Â 28Â Â Â Â 32Â Â Â Â 42Â Â Â Â 56
Find the wrong number in the given number series.
8, 12, 23, 40, 66, 103
8137, 5405, 3669, 2701, 2201, 1997
Find the wrong number in the given number series.
78, 66, 51, 39, 20, 12
2824Â Â Â Â 2314Â Â Â Â Â 1973Â Â Â Â 1759Â Â Â Â 1634Â Â Â Â 1574
In each of the following number series, one term is wrong. Find the wrong term.
3, 7, 13, 21, 31, 42, 57
Find the wrong term in the given series below.
2847, 2954, 2799, 3088, 2727, 3256
Find the wrong number in the given number series.
2, 5, 10, 17, 26, 38, 50