Question 1164151

How to find the number?  The units digit of a two-digit number is three more
than the tens digit.The number is equal to four times the sum of the digits. Find the number. (Hint: We can represent a two digit number as 10t+u.)
<pre>Let tens and units digits, be T and U, respectively
Then we get: U = T + 3 ------ eq (i)
Also, {{{matrix(6,3, 10T + U, "=", 4(T + U), 10T + U, "=", 4T + 4U, 10T - 4T, "=", 4U - U, 6T, "=", 3U, 6T/3, "=", U, 2T, "=", U)}}}
2T = T + 3 ------ Substituting 2T for U in eq (i)
2T - T = 3
T, or tens digit = 3

U = 3 + 3 ------ Substituting 3 for T in eq (i)
U, or units digit = 6
{{{highlight_green(matrix(1,2, "Number:", 36))}}}