Question 1133754
Let Kenny be K, Bala B, and Mike M. And since their ages are unknown, let c be the constant.
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1) 
B = 1c
K = 2c
M = 30
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Let's find their constant difference.
Difference in age between K and Bala = 1c
Difference in age between Mike and K = 30-2c
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2)
B = 21
K = 21+1c (from above, we know the constant difference between B & K = 1c)
M = 2(21+1c) = 42 + 2c (Mike is twice of K)
Difference between M & K = 42+2c - (21+1c) = 21+1c
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30-2c = 21+1c
30-3c = 21
3c = 30 - 21 = 9
1c = 3
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So what's B's age when M = 62? Well, first we have to find the constant difference between B and M.
M - B = 30 - 3 = 27
So if M = 62, B = 62-27 = 35 This is your answer, when Mike is 62 Bala is 35