.
This problem is good for mental solution in couple of lines.
Indeed, in 10 years from now, Ral will be twice Shein's age, and the sum of their ages will be 28+10+10 = 48.
If one of the numbers is twice the other number and their sum is 48, then the numbers are 16 and 32:
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| it is how a human brain should react automatically on such information |
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Hence, the Ral age is 16-10 = 6 years now,
while the Shein age is 32-10 = 22 years now.
Solved.