Question 771315
Let x = age of the father now

And y = age of the son now

Then x = y  +28

x-10 = 15(y-10)

Then:

x = 10+15(y-10) = 10+15y-150 = 15y.140

15y-140 = y +28

14y = 168

y = 12

x = 40

Answer: 40 years old

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