Let x be a two-digit number whose tens digit is t and whose units

Question

Let x be a two-digit number whose tens digit is t and whose units digit is u. What is the value of x?

(1) x is a multiple of 15.
(2) The sum of the digits t and u is 9.

Kudos for a correct  solution .

balamoon · Answer

Solution -

(1) x is a multiple of 15. ---> x can be 15, 30, 45, 60, 75, 90. Not Sufficient.
(2) The sum of the digits t and u is 9. x can be 18, 27, 36, 45, 54, 63, 72, 81, 90. Not sufficient.

1+2 --> There are two common values 45 and 90 matches the x. Not sufficient. ANS E.

ENGRTOMBA2018 · Answer

Given : x= tu with t not equal to 0, x=?

Per statement 1, x = 15p ----> x = 15, 30, 45, 60 ....etc. Thus not sufficient.

Per statetement 2, t+u = 9

The different values for {t,u} can be:

9,0
1,8
2,7
3,6
4,5
5,4
6,3
7,2
8,1

Thus this statement is not sufficient

Combining, we see that possible values can be 45 or 90 and thus even combining the statements is not suffiicient. Thus E is the correct answer.

Priyank38939 · Answer

tens digit is t and and unit digit is u.
1. x is a multiple of 15.
than the unit digit of the x must be 0 or 5.and there are many possible values for it.Not sufficient.
2.sum of digit t and u is 9.
possible values for x is 18,27,36,45,54,63,72,81,90. Not sufficient.
(1)+(2) 
In this case there are 2 possible value for x. 45 and 90.so insufficient.
and hence ans is E

sarkarnitdgp · Answer

Answer is C.

Statement 1 : 
15k = 10t + u
I.e the number must end with either 0 or 5 . clearly. It is not sufficient.

Statement 2:
T + u = 9
(1,8) (8,1) (2,7) (7,2) (3,6)(6,3)(4,5)(5,4). It is not sufficient

Combine 1 and 2: only 1 set I.e (4,5) satisfies both.
Hence C.

ashokk138 · Answer

St 1: x is a multiple of 15

Two digit no. multiple of 15 are 15, 30, 45, 60, 75, 90. Many values for x. Hence Not Sufficient.

St 2: Sum of the two digits is 9 => 18, 27, 36, 45, 54, 63, 72, 81, 90. Many values for x. Not Sufficient.

Combining two statements, we still have two numbers 45, 90 which satisfy both statements..

Hence Not Sufficient.

Option E

KS15 · Answer

Statement 1: x is a multiple of 15. Eg:15,30,45,60,75,90 and so on. Insufficient
Statement 2: sum of t and u is 9. Eg:45,36,63,90 and so on. Insufficient
Even using both statements, x can be 45,90 etc. 
Answer E

Bunuel · Answer

800score Official Solution:

(To understand units and tens, in 75 7 is tens and 5 is units.) Two-digit numbers are the integers from 10 to 99. Statement (1) alone is not sufficient since there are six possible multiples of 15: 15, 30, 45, 60, 75, 90.

Statement (2) alone is not sufficient either, since all multiples of 9 between 18 and 99 will have digits that add up to 9.

Taken together, the two statements are still insufficient. Both the numbers 45 and 90 will satisfy the conditions of the two statements. Because there are two possible answers, we do not have sufficient information to determine the two-digit number.

Since both statements are insufficient, even combined,  the correct answer is choice (E) .

bumpbot · Answer

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Let x be a two-digit number whose tens digit is t and whose units

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