Replace the symbols * and # in 9586*4# so that it is divisible by both 8 and 5.
2024
Replace the symbols * and # in 9586*4# so that it is divisible by both 8 and 5.
- A.
0, 0
- B.
1, 0
- C.
0, 5
- D.
1, 5
Attempted by 51 students.
Show answer & explanation
Correct answer: A
Answer: * = 0, # = 0
Explanation:
Step 1 — divisibility by 5: The last digit must be 0 or 5, so # is either 0 or 5.
Step 2 — divisibility by 8: A number divisible by 8 must be even, so the last digit cannot be 5. Therefore # = 0.
Step 3 — now check the last three digits to test divisibility by 8. The last three digits are '*40'.
If * = 0, last three digits = 040 which equals 40, and 40 ÷ 8 = 5, so it is divisible by 8.
If * = 1, last three digits = 140 and 140 ÷ 8 = 17.5, so it is not divisible by 8.
Conclusion: The only pair that makes the number divisible by both 5 and 8 is * = 0 and # = 0.