You do 90 sit-ups in 2 minutes .Your friend does 126 sit-ups in 2.8 minutes .Do these rates form a proportion? Brainiest

Yes

Step-by-step explanation:

90/2 = 45

126/2.8 = 45

Therefore these rates do form a proportion

Step-by-step explanation:

so we will find the number of sit-ups the friend should do, if it is a direct proportion

let the number of friend's sit-ups be x

2   : 2.8

90 : x

cross multiply

we get x=126 sit-ups

so the rates do form a (direct) proportion

only 10/60 isn't equivalent

hope this : )

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

the answers might not be correct use at own risk