



 
Hi Simon, If I have this equation to solve \[2 \frac12 (x  1)  \frac{x+3}{3} = 4\] I would first write the mixed number $2 \frac12$ as an improper fraction, that is $2 \frac12 = \frac52.$ Thus the equation becomes \[\frac52 (x  1)  \frac{x+3}{3} = 4\] Now I hope you can see why you multiply by $2,$ to eliminate the $2$ in the denominator. Multiplying by $2$ on both sides gives \[5 (x  1)  2 \times \frac{x+3}{3} = 2 \times 4\] Now multiply by $3$ to remove the final fraction and then solve the resulting equation. I hope this helps,  


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