Let a mean minus (−), b mean multiplied by (×), C mean divided by (÷), and D…
2012
Let a mean minus (−), b mean multiplied by (×), C mean divided by (÷), and D mean plus (+). After replacing the letters, evaluate strictly from left to right. The value of 90 D 9 a 29 C 10 b 2 is:
Answer: D. 14 — ConceptIn a coded-operation expression, first replace each letter with the operation assigned to it. When left-to-right evaluation is specified, perform each…
- A.
8
- B.
10
- C.
12
- D.
14
Show answer & explanation
Correct answer: D
Concept
In a coded-operation expression, first replace each letter with the operation assigned to it.
When left-to-right evaluation is specified, perform each resulting operation sequentially without reordering by ordinary precedence.
Application
Replace D with +, a with −, C with ÷, and b with ×. The expression becomes 90 + 9 − 29 ÷ 10 × 2.
Start from 90: 90 + 9 = 99.
Continue from the running result: 99 − 29 = 70.
Next, 70 ÷ 10 = 7.
Finally, 7 × 2 = 14.
Cross-check
Reverse the last two operations: 14 ÷ 2 = 7, and 7 × 10 = 70. These reproduce the preceding running totals, so the value is 14.