CAT 1991 — QA Question 37
MiscellaneousEasy
A calculator has two memory buttons, A and B. Value 1 is initially stored in both memory locations.
The following sequence of steps is carried out five times:
- add 1 to B
- multiply A to B
- store the result in A
What is the value stored in memory location A after this procedure?
Answer & solution
Correct answer: 720
- A
120
- B
450
720
- D
250
Solution
| A | B | Step I (B + 1) |
Step II (A × B) |
Step III A |
Step III B |
|
|---|---|---|---|---|---|---|
| Beginning | 1 | 1 | ||||
| 1st time | 1 | 1 | B = 2 | (1 × 2) = 2 | 2 | 2 |
| 2nd time | 2 | 2 | B = 3 | (2 × 3) = 6 | 6 | 3 |
| 3rd time | 6 | 3 | B = 4 | (6 × 4) = 24 | 24 | 4 |
| 4th time | 24 | 4 | B = 5 | (24 × 5) = 120 | 120 | 5 |
| 5th time | 120 | 5 | B = 6 | (120 × 6) = 720 | 720 | 6 |
Hence, option (c).