Before adding dissimilar fractions (fractions with different denominator), you have to make the fractions similar first. To make the fractions similar, find the Least Common Multiple of the denominator. In this case, the LCM is 10. Then rewrite the fractions using the LCM as the denominator.
9/10 = 9/10; 4/5 = 8/10
You can now proceed with addition -
9/10 + 8/10 = 17/10 or 1 7/10
2/4 of an hour is half an hour so 2/4 of an hour is 30 minutes. Hope it helps
Answer:

Step-by-step explanation:
Lets use the compound interest formula provided to solve this:

<em>P = initial balance</em>
<em>r = interest rate (decimal)</em>
<em>n = number of times compounded annually</em>
<em>t = time</em>
First, change 6% into a decimal:
6% ->
-> 0.06
Since the interest is compounded semi-annually, we will use 2 for n. Lets plug in the values now and your equation will be:

b. One hundred and fifty (150) square feet
To find the mean you add all the numbers and divide by how many numbers there are so in this case 2+3+4+4+6= 19, there are 5 numbers so divide 19/5