Answer: 16 years old
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Explanation:
Tahir's age is 32, and Bina is one fourth of Tahir's age. That means Bina must be 8 years old because (1/4)*32 = 32/4 = 8.
Seema and Arshad are the same age, which is unknown for now. Let's call that unknown age x.
The ratio of Seema's age to Tahir's age is x:32 which we can write in the fraction form x/32.
The ratio of Bina's age to Arshad's age is 8:x or 8/x
We're told the two ratios are equivalent, so we'll set those fractions equal to one another and solve for x.
x/32 = 8/x
x*x = 32*8
x^2 = 256
x = sqrt(256)
x = 16
Seema and Arshad are both 16 years old.
Note that x:32 updates to 16:32, which then can be fully reduced to 1:2
The ratio 8:x updates to 8:16 and that reduces to 1:2 as well, which shows that 16:32 and 8:16 are equivalent ratios (the second part of the ratio is double that of the first part).