The original perimeter is 22 cm.
If both sides are doubled, the length would be 16 cm and the width would be 6 cm.
The perimeter would be 44 cm.
22/44 is 50%.
If you're asking how to simplify, then this is how you do it.
when a power meets another power but in brackets, then you have to multiply the powers. ¼ × 4 would be 1. i simplified 81 to 3⁴.
Frank can build a fence in twice the time it would take Sandy. Working together, they can build it in 7 hours. How long will it take each of them to do it alone?
Answer
If Frank and Sandy can build the fence in 7 hours, they must be building
1
7
of the fence every hour.
Now, let the amount of time it takes Sandy be
x
hours so that Frank takes
2
x
hours. Sandy can build
1
x
of the fence every hour and Frank can build
1
2
x
of the fence every hour.
We now have the following equation to solve.
1
x
+
1
2
x
=
1
7
2
+
1
2
x
=
1
7
21
=
2
x
x
=
21
2
=
10.50
Thus, Sandy takes
10.50
hours and Frank takes
21
hours.