An event coordinator has a budget of $680. If she spent $75 on balloons and $65 on invitations, what percent of her budget does she have left?

Step 1: Calculate Part (Non-100%)
In reading the prompt, the first step is to identify the amounts needed to be added to calculate the portion of the budget that has already been spent, which represents the part (non-100%).
75 + 65 = 140
Making 140 the part (non-100%).
Step 2: Divide the Part (Non-100%) by the Whole (100%)
In order to find the percentage, we have to divide the part of the total available amount by the total amount available. In this case, the non-100% part that we have, 140, will be divided by the total amount available that represents 100%, which is 680.
140÷ 680 = 0.2058823529
We can round this off to the third-place value. Check your answer choices to see if numbers were rounded to a different place value.
So let’s look at the third place value:
0.2058823529
We look to the right and see an 8. Since an 8 is 5 or more, that means the underlined digit goes up by one so the 5 becomes a 6.
0.206
Every other number to the right of the 5 would turn to 0, and since they would have no value, we can get rid of them.
Step 3: Multiply by 100
Now that we have our decimal, we have to turn it into a percent. Remember, we turn a decimal into a percent by multiplying it by 100, which is the same as moving the decimal point two spots to the right.
0.206 × 100 = 20.6%
This tells us how much of the budget has already been spent. Finally, we have to find the percentage of what she has left.
Step 4: Subtract Budget Spent from Total Budget
The event coordinator spent 20.6% of her budget. In order to find the percentage that is left we will subtract the percentage she spent from 100%.
100% – 20.6% = 79.4%
The event coordinator has 79.4% of her budget left.