I thought of a two-digit number. The unit digit of my number is a prime number, and the tens digit is four times as big as the u

Question

liubo4ka [24]

4 years ago

9

I thought of a two-digit number. The unit digit of my number is a prime number, and the tens digit is four times as big as the u

nit digit. What is my number?

Mathematics

1 answer:

denis-greek [22] · Answer 1 · 2021-11-14T17:09:12+03:00

denis-greek [22]4 years ago

4 0

let the number is 10x + 3.

then sum of its digits = x + 3.

from given condition, we have

x+3 = (1/7)* (10x + 3)

=> 7x + 21 = 10x + 3

=> 3x = 18

=> x = 6

therefore the number is 63.