If t represents the tens digit of a two-digit number, and u represents the units digit, what expression represents the number?

Question

Answer choices are:

A. t+u

B. 10t+u

C. 10u+t

D. 10(t+u)

E. tu

Answer 1

For a question like this (especially common on the GRE or GMAT, but also very occasionally seen on the ACT), the general technique is always to:

1.) multiply the units digit by 1, the tens digit by 10, the hundreds digit by 100, and so on (each digit being multiplied by the multiple of ten corresponding to its place in the number)

2.) and then add all of the terms.

This matches the way digits in a number take their actual position within the number - for example, the number 543 equals (5 x 100) + (4 x 10) + (3 x 1).

So in this case, you would take (t x 10) + (u x 1) to get 10t + u. The answer is B.

Answer 2

10t + u

 

The correct answer is (B).

Answer 3

The answer is E.

 

Take the number 52 for example. You have 5 sets of ten and you have 2 sets of 1 (the unit number).

 

Therefore, 5 would be t and 2 would be u.

 

tu.