Question

Lamar is taking a stunt man training course. he scored a 99 on his first test, but he only scored an 85 on his second test. what is the lowest score that lamar can make on his third and final test in order to have an overal average of 90?

Answer 1

86

Explanation:

Let x be the required score for Lamar's third test in order to get an average of 90 or higher.

Start with the initial equation:

`(99+85+x)/(3)\geq 90`

Simplify the numerator in the fraction:

`(184+x)/(3)\geq90`

Multiply both sides by 3 to cancel out division on left side of equation:

`184+x\geq 270`

Subtract 184 from both sides to isolate the x variable:

`x\geq86`

Leaving us with x must be greater than or equal to 86.

Answer 2

86.

Explanation:

His total score is 99 + 85 + x where x is score on third test,

99 + 85 + x = 3 *90 (as his average must be 90, so:

184 + x = 270

x = 270 - 184

= 86.