<span> 20% of 40 is 8. so 40</span>
To get the answer we can use proportion
40$ ------------- 100%
2$ ---------------- x
crossmultiply now
40x=2*100 /:40
x=200:40
x=5% - its the answer
If a coral reef grows at a steady rate every week, then to find how much it grows in 12 weeks, we need to multiply the growth rate by 12 weeks. Also, since we want our answer in centimeters, we can change the growth rate to centimeters. 0.15m = 15cm
15cm * 12 = 180cm
The coral reef will grow 180cm in 12 weeks.
Answer:

Step-by-step explanation:
Given

Required
Determine the solution
Since b is a perfect square, the equation can be expressed as:

Apply difference of two squares:

Split:

Remove brackets:

Make a the subject in both equations

The solution can be represented as:

The last one is right because it’s per 1 unit or in this case day