original number in first box --- x
original number in 2nd box --- 123-x
after shift:
first box ----- x-10
2nd box --- 123-x + 10 = 133-x
133-x = 2(x-10)
solve for x
In two box 123 coins. Ten coins from a first box shifted to the second box. The second box now having twice as many coins in the first box. How many coin in the first box before the shift?
1 answer