If we are scaling up the surface area by a factor of 10 means that the two dimensions of area are each being increased by 10 times the original size. Therefore, the surface area is increased by a factor of 10 x 10, or by a factor of 100.
Ayou do it the exact same as whole number fractions but you might have to be more mindfull of the decimals
Step-by-step explanation:
where's the rest of question so I can help?
The answer is 40 is 80% of 50 ☺