For this problem, you need to create a proportion.
40 inches/12 minutes=100 inches/x
Let x be the number of minutes it takes to weave 100 inches
Solve
40x=1200
x=30 minutes
6 X 89 =6 x (80 + 9) = (6 x 80)+ (6x9)=480+54=534
The answer above is mostly correct, HOWEVER The ellipse is a vertical ellipse and therefore uses the equation (x^2/b^2)+(y^2/a^2)=1
a=10/2=5
b=8/2=4
put it in the equation and it is (x^2/4^2)+(y^2/5^2)=1
Simplify and the answer is (x^2/16)+(y^2/25)=1