Difficulty Level : High
Time to Solve : <60 secs
Please discuss your approach and also provide time you took to solve the question. OA will be posted only when enough people have outlined their approach.
Q. What is the sum of digits of the number N given by N = 10^35 - 75?
A) 313
B) 295
C) 372
D) 304
E) None of these
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Choice D; took 20 seconds
there are 35-2 9s in 10^35 - 75 and a 2 and a 5
so the answer is 9*33+2+5 = 304
d
I will go with D. Its 304. Took 70 minutes. hopefully the rigth answer
Answer: D
Say 10^5 - 75 = 99925. Therefore substract 2 digits from raise to power i.e. 35.
9 x 33 + 2 + 5 = 304
Time: 15 sec
My ans is 295
10^35 - 75
9*32 + 2 +5 = 295
u will be left wid 32 9's not 33
eg; consider 1000-75 = 925
ie there will be only 1 nine coz 1 will be gone off as a borrow
Nope, it has to be d. Explanation already provided in multiple places.
1000-75 = 925
10000-75=9925
100000-75=99925
etc etc
3 zeros yields 1 nine
4 zeros yields 2 nines
5 zeros yields 3 nines
etc etc
difference is 2.
In other words, 10^35 -75 has 33 9's.
yeah i figured tht out after submitting
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