M4maths
Maths Puzzle
Numerical Ability
Number System
P is an integer P883 If P-7 is a multiple of 11 then the largest number that will always divide P4 P15 is Op 1 11 Op 2 121Op 3 242 Op 4 None of these
Read Solution (Total 1)
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- OPTION C: 242
P > 883
P − 7 > 876
The smallest number after 876 that is a multiple of 11 is 880 = 11*80
So P = 11k+7, for some integer k ≥ 80
(P+4)(P+15)
= (11k+7+4) (11k+7+15)
= (11k+11) (11k+22)
= 11(k+1) * 11 (k+2)
= 121 (k+1)(k+2)
Now when k is even, then k+2 is even, so (k+1)(k+2) is even
and when k is odd, then k+1 is even, so (k+1)(k+2) is even
(k+1) (k+2) = 2n, for some integer n
(P+4)(P+15)
= 121 (k+1)(k+2)
= 121 * 2n
= 242n
- 9 years agoHelpfull: Yes(7) No(2)
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