Answer:
24.6 % decrease
Step-by-step explanation:
Let x be the original temperature
Increase by 25%
x + .25x
1.25x
Decrease by 40%
The amount decreased is
(1.25x) *.40
.496x
Subtract that from 1.25x
1.25x - .496x
.754x
We need to find the percent decrease
1 - .754 = .246
24.6 % decrease
Given:
First side(A): 2B - 7
Second side(B): B
Third side(C): B + 4
Plug in values:
A + B + C = 80
2B - 7 + B + B + 4 = 80
If you look at the coefficients only, you can rewrite the equation like this:
2B + B + B - 7 + 4 = 80
This means that 4B - 7 + 4 = 80
=4B - 3 = 80
= 4B = 80 + 3
B = 83/4, so you can either write B as 83/4 or as 20.75.
Checking your work:
A: 2(20.75) - 7 = 34.5
B: 20.75
C: 4 + 20.75 = 24.75
34.5 + 20.75 + 24.75 = 80cm.
Hope this helped.
7/8 x = 21
7x = 21×8
7x = 168
x = 24
Answer:
5
Step-by-step explanation: