a student chose a number , multiplied it by 2 , then subtracted 138 from the result and got 104 . what was the number he chose ?
"let xx be the number he chose , then 2 â ‹ … x â ˆ ’ 138 = 104 2 â ‹ … x â ˆ ’ 138 = 104 x = 121 answer : b"
divide(add(104, 138), 2)