What do I need on my exam to get a 80% final grade

My grade right now is a 75%. The final exam is worth 25% of my total grade. What do I need on my final exam to get an 80% final mark? Thanks.

Calculate a weighted average:

(0.75 * 75%) + (0.25 * x%) = total grade

Substitute 80% for the total grade and solve for x:

(0.75 * 75%) + (0.25 * x%) = 80%

56.25% + 0.25x = 80%

Subtract 56.25% from 80%:

0.25x = 23.75

Divide both sides by 0.25:

x = 23.75 / 0.25 = 95%

A 95% (or above) will bring you up to (or above) an 80% grade for the course.

A 100% grade on the final will get you an 81.5% grade for the course.

.75 * .75 + .25x = .8
.5625 + .25x = .8
.25x = ,2375
x = .95

you need 95% on the final to get 80% in the class

3/4 x 75 + 1/4 x n = 80
225 + n = 320
n = 95, your needed final exam grade to get 80% overall

You will need to get 95% on your final.

.75(75)+.25(x)=.80
56.25 +.25x=.80
.25x = 23.75
x = 95

The answer is 20%

You already have 75%, you need 80%, so you need to gain an additional 5% from the final.

5 is 20% of 25.