Practice Test: Exponential Functions IMCE3M
7. After being sprayed by ant-killer, the number of ants in a mound decreases by half (50\%) every hour. If there were originally $1,000,000$ ants in the mound...
a) Determine a model for the amount of ants left after " $x$ " hours.
\[
A=\left(-^{x}\right)
\]
b) How many ants are left after half of a day?

Answer

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Answer

b) After half of a day (12 hours), there are approximately $\boxed{244}$ ants left in the mound.

Steps

Step 1 ：a) The model for the amount of ants left after "x" hours is: \[A = 1,000,000 * (0.5^x)\]

Step 2 ：b) After half of a day (12 hours), there are approximately $\boxed{244}$ ants left in the mound.