A is the brother of B. B is the brother of C. D is the father of A. Based on these three statements, which of the following statement cannot be definitely true?

Option (D)

A is the brother of B and B is the brother of C. So, C may be the brother or sister of A.

20 women can do a work in 15 days and 15 men can complete a work in 12 days. What is the ratio between the capacity of men and women?

(20*15) women can do a work in 1 day.

So women 1 day =1/300

(15*12) men can do a work in 1 day

So men 1 day work=1/180

So, required ratio=(1/300)/(1/180)

=(1/5)/(1/3)

=3/5

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John can complete a journey in 19 hours. He travel first half of the journey at the rate of 21 kilometre per hour and second half at the rate of 24 km per hour. Find the total journey in kilometre?

Let the total distance b x kilometre. Then,

15x=168x20

x=[(168x20)/15]=224 km.

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