If a = c • 10^b and a and b are integers, what is the value of b? (1

Question

If a = c • 10^b and a and b are integers, what is the value of b?

(1) c has nonzero digits in only the tenths, hundredths, and thousandths places.
(2) 1 < b < 4

msk0657 · Answer

Stat 1: Let c = 123.xyz ( here x,y and z tenths, hundredths, and thousandths places respectively)

c • 10^b = a , in order to get a as an integer then b has to be 3, but we don't have such clear information about b...NS.

Stat 2 : b can be 2 or 3...but here we aren't told about c value...NS.

Both: When b = 2 we get a = 123x.yz and this is not a integer.

When b = 3 we get a as integer...Sufficient.

Option C.

mdacosta · Answer

i think the question should be reworded. I interpreted 'tenths, hundreds, and thousands' places as 1 234 5 (e.g., not as decimals). or am i just slow?

Nunuboy1994 · Answer

The suffix "th" as in hundredths, thousandths refers to decimal places. You're thinking of "ones place, tens place, hundreds place" in which case the answer would be "E." This is a very fixable issue- this is just an issue of forgetting rules and not so much any lapse in logic.

Bunuel · Answer

1234.567

1 - THOUSAND S 
2 - HUNDRED S 
3 - TE NS 
4 - UNITS
. -  decimal point 
5 - TEN THS 
6 - HUNDRED THS 
7 - THOUSAND THS

Notice the difference between TE NS  and TEN THS .

KanishkM · Answer

from 1, we get to know that

c will be taking values such as 0.123, 0.125, 0.126

from 2) we get to know that only 2 and 3 are the available test cases, to take the value of 10^b

Now when we combine only one value satisfies the if condition

b = 3

If a = c • 10^b and a and b are integers, what is the value of b? (1

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