Help with a math question....?

Question

okay... i'm translating this from japanese to english, so i dunno how much you're gonna understand... but plz try...

There is a two-digit number. The sum of the tenth number (the one on the left... like in 10 it is 1) and the ones number (like in 10 it is 0) is 9. The tenth number is 1 more than 3 times the ones number.

What are the two numbers in the number?

Answer 1

You just asked this, and I just answered it. :)

The answer is 72.

Click link to see this problem solved.

Answer 2

Let's try to put that into the form of a mathematical equation. We'll call the tenth number T and the ones number O. We're told that T + O = 9, and that T = 3O + 1. Substitute the second equation into the first one, and you get 3O + 1 + O = 9. That simplifies to 4O + 1 = 9. Subtract 1 from each side: 4O = 8. Divide by 4: O = 2. Now, go back to the first equation: T + O = 9. Set O = 2: T + 2 = 9. Subtract 2: T = 7.

The number is 72.

Answer 3

Let's call the number TE, where T is the tens digit and E is the ones digit. Then the sum of the tens and ones digit is nine, i.e. T + E = 9. You also have that T is one more than three times E, i.e. T = 3E + 1.

Given these two equations, we can solve:

T + E = 9
(3E + 1) + E = 9
4E + 1 = 9
4E = 8
E = 2.

And then we can infer that T = 7. So the number is 72. Cheers!

Answer 4

oh man, it's been too long.

x=digit in tens place, y=digit in ones place

x+y=9
x=1+3y
so: from the first equation x=9-y

substituting in the 2nd equation: 9-y=1+3y or 8=4y => 2=y
and plugging 2 in for y in the first equation yields 7 for x

seems to satisfy the requirements

Answer 5

Its 72. 7+2 is 9 and 7 is (3x2) +1.

Answer 6

Let t equal tens place and w equal ones place.
t+w=9
t=3w+1
Substitute first equation into second: 9-w=3w+1
8=4w
w=2, t=7
Number is 72

Answer 7

x=tens, y=ones

x+y=9
x+1-3y=0

subtract 1st equation from 2nd:
1-4y=-9
4y=8
y=2

substitue this y into 1st equation:
x+2=9
x=7