So,
Let's translate this into mathematical form.
"9/10 times a number"
\(\frac{9}{10} n\)
"plus 6 is 51"
+ 6 = 51
So we have our equation:
\(\frac{9}{10} n + 6 = 51\)
Subtract 6 from both sides.
\(\frac{9}{10} n = 45\)
Multiply both sides by the reciprocal of 9/10 (10/9).
\(n = (45) \frac{10}{9}\)
Multiply.
\(\frac{45}{1} * \frac{10}{9} --\ \textgreater \ \frac{5}{1} * \frac{10}{1} = 50\)
The number is 50.
Check.
\(\frac{9}{10} * 50 + 6 = 51\)
Multiply.
\(45 + 6 = 51\)
Add.
\(51 = 51\)
This checks.
S = {50}
