9 days ago, the mold covered an area of 
.
Today (after 9 days), the mold covers an area of 
.
<em>What is the increase in area?</em> It went from 3 to 9. So the increase is 
.
Now, we need to find <em>rate of change</em>. It means to find how much the area increased every day over the past 9 days. We simply divide <em>the increase (6)</em> by the <em>total number of days (9)</em> to find the rate per day. So we have,
ANSWER: Change of Rate = 
per day
Answer:
Quincy read 9 books.
Step-by-step explanation:
Work backwards. Samantha read three less books than Teresa (11-3=8). Ralph read half as many books as Samantha (8/2 = 4). Quincy read five more books than Ralph (4 + 5 = 9).
Answer: 0.6 cm
Step-by-step explanation:
Given : Over the past 4 years, Grandpa Ernie's height decreased by a total of 2.4 cm.
If the height is decreased by the same amount each year.
Then, the change in Grandpa Ernie's height each year will be =
Total decrease in height ÷ 4
= 2.4 cm ÷ 4 = 0.6 cm
Hence, the change in Grandpa Ernie's height each year = 0.6 cm
<em>54</em>
- Step-by-step explanation:
<em>- 2n(5 + n - 8 - 3n) =</em>
<em>replace n = 3</em>
<em>- 2(3)(5 + 3 - 8 - 3×3)</em>
<em>= - 6(8 - 8 - 9)</em>
<em>= - 6(0 - 9)</em>
<em>= - 6 × - 9</em>
<em>= 54</em>
<em>(-)(-) = +</em>
