Question

The swimming team has competed in 45 races this season. They have won 30 races so far. How many races will the team need to win today for the team to have a 75% success rate?
Pls help soon, will Mark brainliest

Answer 1

Answer:

15 races

Step-by-step explanation:

The team has competed in 45 and has won 30. So the success rate is:

Success rate is:

$Sccess\ rate=r= \frac{30}{45}*100\\ =66.7\ percent$

We have to find the number of races the team needs to win for 75% success rate

Which means that

$r = \frac{30+x}{45+x} = 0.75$

We have to solve the equation for x

$\frac{30+x}{45+x}=0.75\\ 30+x = 0.75(45+x)\\30+x=33.75+0.75x\\x-0.75x=33.75-30\\0.25x=3.75\\x=\frac{3.75}{0.25}\\ x=15$

The team needs to win 15 races to get 75% success rate ..