Solve for x
x=21
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18\times \frac{10}{9}=x-1
Multiply both sides by \frac{10}{9}, the reciprocal of \frac{9}{10}.
\frac{18\times 10}{9}=x-1
Express 18\times \frac{10}{9} as a single fraction.
\frac{180}{9}=x-1
Multiply 18 and 10 to get 180.
20=x-1
Divide 180 by 9 to get 20.
x-1=20
Swap sides so that all variable terms are on the left hand side.
x=20+1
Add 1 to both sides.
x=21
Add 20 and 1 to get 21.
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