Matt started doing extra chores around the house and his allowance changed from $30 per week to $40 per week. What is the percent of change in Matt's allowance?

25% increase

20% increase

33.3% increase

10% increase

33.3%

Step-by-step explanation:

Let's say the percent change is x%. Then the equation is:

30 + x% * 30 = 40

Subtract 30 from both sides:

x% * 30 = 10

Divide by 30:

x% = 10/30 = 1/3

Remember that % simply means "out of 100", so:

x/100 = 1/3

Multiply both sides by 100:

x = (1/3) * 100 = 33.3%

33.3% increase

Step-by-step explanation:

Change: final - initial

= 40 - 30 = 10

%change

10/30 * 100

100/3 %

Approximately 33.33%