Question 1184142

Peter had 3/8 as many marbles as Simon. After Simon misplaced 3/4 of his marbles, Peter had 120 more marbles than Simon. How many marbles did Peter have?
<pre>With Peter (P) having {{{3/8}}} of marbles that Simon (S) has, Simon (S) would have: {{{matrix(1,4, (8/3)P, or, 8P/3, marbles)}}}
Since Simon misplaced {{{3/4}}} of his marbles, he would have: {{{matrix(1,3, (1/4) * (8P/3), or, 2P/3)}}} left
With Peter (P) now having 120 more marbles than Simon, we get: {{{matrix(1,3, P, "=", 2P/3 + 120)}}}
3P = 2P + 360 ------ Multiplying by LCD, 3
Original number of marbles Peter had, or {{{highlight_green(matrix(1,3, P, "=", 360))}}}