Question

1. carolyn is searching online for tickets to a concert. two weeks ago, the cost was $30. now the cost is $39.

a. what is the percent increase?
b. what would be the percent increase if the ticket agent charges an additional $4.50 fee with the new ticket price?

1. the seventh - grade class is raising money to have a class trip at the end of the year. they began the year with $1,500. now they have $1,650 in the account.

a. what is the percent of increase for the money the class has raised?
b. make sense and persevere the class figured out that if the percent increase is 99% from the beginning of the year, the class will have enough money for every student to go on the field trip. how much money will the class need to raise for every student to go.

Explanation:

Step1: Calculate the amount of increase

For problem 7a: The original price is $30, and the new price is $39. The increase amount is $39 - $30 = $9.
For problem 9a: The original amount is $1500, and the new amount is $1650. The increase amount is $1650 - $1500 = $150.

Step2: Calculate the percent increase

The formula for percent increase is $\frac{\text{increase amount}}{\text{original amount}}\times100\%$.
For problem 7a: $\frac{9}{30}\times100\% = 30\%$.
For problem 9a: $\frac{150}{1500}\times100\% = 10\%$.
For problem 7b: The new price with fee is $39 + $4.50 = $43.50. The increase amount is $43.50 - $30 = $13.50. Then $\frac{13.50}{30}\times100\% = 45\%$.
For problem 9b: If the percent increase is 99%, using the formula $A=P(1 + r)$ (where $P$ is the original amount, $r$ is the rate of increase as a decimal). Here $P = 1500$, $r=0.99$. So $A = 1500\times(1 + 0.99)=1500\times1.99 = 2985$.

Answer:

7a. $30\%$
7b. $45\%$
9a. $10\%$
9b. $\$2985$