A student chose a number, multiplied it by 8, then subtracted 138 from the result and got 102. What was the number he chose?  Choose the correct choice:
A) 30  B) 120  C) 130  D) 140  E) 150

Rationale: "solution : let xx be the number he chose , then 8 ⋅ x − 138 = 102 8 x = 240 x = 30 answer a"
Answer: A