can you help me

Question

the width of a poster board is 30 inches. using siccors you reduce the width of the poster board to 10 inches. what is the scale factor of the dialation?

 

 

on a given blue print 1 inch= 12 feet . if the deminsions of a recreation room on the blueprint are 2 inches x 1.75 inches what are the actuall measurements?

Answer 1

Kayla, remember that dialation is always done using multiplication.  Our scale factor times the original gives us the new amount.

 

We went from 30 inches to 10.  What can we multiply 30 by to get 10?  30x = 10.  So, x = 10/30 = 1/3.

 

 

 

The second problem also deals with multiplication.  If one inch is 12 feet, then how many feet is 2 inches?  We had to multiply 1 inch by 2 to get 2 inches, so we multiply 12 feet times 2 to get 24 feet.  We also multiply 1 inch by 1.75 to get 1.75 inches, so we multiply 12 times 1.75 to get 21 feet.

 

Our dimensions are 24 inches x 21 inches.

 

Another way is to set up a proportion. 1 inch/12 feet = 2 inches/ x feet.  Cross multiply. x = 24 feet.  1 inch/12 feet = 1.75 inches/x feet.  Cross multiply.  x = 21 feet.

 

Hope this helps!