Answer:
540 ft cubed
Step-by-step explanation:
Length • width • height
4.5 • 12 • 10
540
"seven" means ' 7 '
"two" means ' 2 '
"the quantity seven plus two" means ' (7 + 2) '
"one hundred times the quantity ..." means ' <em>100 (7 + 2)</em> '
That's the expression.
One of the rules for handling these things is that you should always
take care of anything inside parentheses first. So do that.
(7 + 2) = 9
Now you can can write the expression like this: ' 100 (9) ' .
That's just <em>900 .
</em>
They will get to 90 feet at <u>half a minute</u> or <u>30 seconds</u>.
y = a(1-r)^×
source: https://mathbitsnotebook.com/Algebra2/Exponential/EXGrowthDecay.html
y = exponential decay
a = initial amount = 78000
r = decay rate = .03
x = number of time intervals = w
Error:
b = growth/ decay factor
b = 1+r for growth
b = 1-r for decay
x = w per the above information
Sarah did not account for either of these points when creating her equation.
Correct solution:
y = 78000 (1-.03)^w