Answer:
12 or 13. See below Use 12 first then 13
Step-by-step explanation:
Write the proportion
3:7 = x:(x + 5) Write the proportion in fractional form.
3/7 = x / (x + 5) Cross multiply
3*(x + 5) = 7x Remove the brackets
3x + 15 = 7x Subtract three x from both sides.
3x - 3x + 15 = 7x - 3x Collect like terms
15 = 4x Divide both sides by 4
15/4 = 4x/4 Divide
3.75 = x The question is when to round and how.
The total number of competitions was x + x + 5 = 2x + 5
total = 2*3.75 + 5
total = 7.5 + 5
Total = 12.5 which I would round to 12. If that does not work, use 13. You round at the end.
