Answer:
GCF= 1
LCM= 1680
Step-by-step explanation:
GCF= Find the prime factorization of 21, 21 = 3 x 7
Find the prime factorization of 80, 80 = 2 x 2 x 2 x 2 x 5
Then multiply the prime factors both numbers have in common
LCM= multiply the two numbers together and ignore all negative signs
The amount of fabric needed to cover 8 blocks is 192cm.
<h3>How much fabric is needed to cover 8 blocks?</h3>
In order to determine the amount of fabric needed, the total surface area of the rectangular prism has to be determined. The total surface area of the rectangular prism is the sum of the areas its faces.
Total surface area of a rectangular prism = 2 (lw + wh + lh)
where:
- l = length
- w = width
- h = height
2 x [(4 x 1/2) + (1/2 x 2) + (4 x2)] = 24cm
Fabric needed fo 8 blocks = 24 x 8 = 192cm
To learn more about rectangular prisms, please check: brainly.com/question/8890358
Answer:

Step-by-step explanation:

T could be located at 15 because 5 plus 15 equals 20
The first step would be to isolate a variable (solve for a variable)....so u will have something to sub into the other equation