Q145
ArithmeticNumber System, LCM/HCF & Divisibility
If the ratio of boys and girls in a city is 7:4, which of the following can not be the total number of boys and girls in the city?
- a.29435417
- b.57463822
- c.28444625
- d.29434526
Answer: (B) 57463822
With boys : girls = 7 : 4, the total must be a multiple of 11. Using the alternating-digit test, 29435417, 28444625 and 29434526 each give 11, so they are divisible by 11. 57463822 gives 9, so it is not a multiple of 11 and cannot be the total.