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vinni.k
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10! + 9! can be rewritten as:
A. 9!(10)
B. 11!/10
C. (10!)^2*9
D. (9!)^2 + 10
E. 19!
OA is B
My approach
10! + 9!
10*9! + 9!
Taking out 9! common
9!(10 + 1)
9!(11)
Now from here i don't know how to proceed. So, i am bit stuck here. However, when i was reviewing, i played around with B
11!/10
(11 * 10 * 9!) / 10
(11)9!
Same outcome as what i got when i solved earlier, but how to get B on my first approach.
Thanks
A. 9!(10)
B. 11!/10
C. (10!)^2*9
D. (9!)^2 + 10
E. 19!
OA is B
My approach
10! + 9!
10*9! + 9!
Taking out 9! common
9!(10 + 1)
9!(11)
Now from here i don't know how to proceed. So, i am bit stuck here. However, when i was reviewing, i played around with B
11!/10
(11 * 10 * 9!) / 10
(11)9!
Same outcome as what i got when i solved earlier, but how to get B on my first approach.
Thanks
