Answer:
78
Step-by-step explanation:
Let x be the score on the next test
We are averaging 6 tests and want an average of 75
( 82+91+38+78+83+x) /6 = 75
Multiply each side by 6
( 82+91+38+78+83+x) = 75*6
( 82+91+38+78+83+x) =450
Combine like terms
x+372 = 450
Subtract 372 from each side
x+372-372 = 450-372
x =78
Answer: x = 20
Step-by-step explanation:
So the figures are the same, except the bigger one is bigger. It's equally bigger on all sides, so basically 6 * y = 15 to find what it is enlarged by. Then multiple 8 by y to find the missing length.
6*y = 15
/6
y = 2.5
8 * 2.5 = 20
We can also check this by:
4 * 2.5 = 10
6 * 2.5 = 15
8 * 2.5 = 20
Non proportional it should be