word problems

[mmarti25]

After lengthening my stride (pace) by 2 inches, I can now walk a mile in 132 fewer paces. What is the lengh of my new stride?



A tinsmith wants to lighten a square of sheet metal 10% by snipping off four small equal isosceles right triangles, one from each corner. If the square is 50cm on each side, what are the legs of the triangles?

 

[Gene]

X is the old length.
X+2 is the new length.
5280*12/X is the number of old strides/mile (to put it into inches.)
5280/(X+2) is the number of new strides/mile.
5280*12/X - 5280*12/(X+2)=132
Solve for X.

The length is X.The area of each triangle is X^2/2.
The area of the sheet is 50^2.
10% of that is .1*50^2.
There are 4 triangles so their total area is 2*X^2.
2*X^2=.1*50^2
Solve for X.

P.S. It would have been better if I had called the new stride X and the old stride X-2 'cause the new stride is what we are looking for.

 

[mmarti25]

Thanks for your help!