Answer:
The total budget for their student film was $540
Explanation:
The total percentage of any quantity is 100%
∵ A group of friends was working on a student film
∵ They spent all their budget on props and costumes
∴ The total budget of the props and costumes = 100%
∵ They spent $243 on props
∵ They spent 55% of the total budget on costumes
→ Find the percentage of the props
∴ The percentage of the props = 100% - 55%
∴ The percentage of the props of the total budget = 45%
→ That means 45% of the total budget = 243
∵ 45% × total budget = 243
→ Change the percent to a number by divide it by 100
∵ 45% = 45 ÷ 100 = 0.45
∴ 0.45 × total budget = 243
→ Divide both sides by 0.45
∴ The total budget = 540
∴ The total budget for their student film was $540