Percentage and Ratio problems.

[d42k7h1257]

1) 8 tins of paint are required for a surface of an area 50m^2 if 4 coats of paint are applied. Find the number of tins of paint needed for an area of 7-m^2 if 5 coats of paint are applied.

[Guest]

1) 8 tins of paint are required for a surface of an area 50m^2 if 4 coats of paint are applied. Find the number of tins of paint needed for an area of 7-m^2 if 5 coats of paint are applied.

The area to be painted has changed by a factor or [tex]\frac{7}{50}[/tex] and the coats of paint have increased by a factor of [tex]\frac{5}{4}[/tex] so the amount of paint needed changed by a factor of [tex]\frac{7}{50}\frac{5}{4}= \frac{7}{40}[/tex].