Question

Ginny's median score on three test was 90. Her mean score was 92 and her range was 6. what were here three test scores?

Answer 1

let x, y, z be the three test scores

`(x+y+z)/(3)=92`

y is the median, y = 90

If the range is 6, then;

z - x = 6

Make z subject of formula from z - x = 6

z = 6+ x

substitute y =90 and z = 6+ x into our first equation and then solve for x

`(x+90+6+x)/(3)=\text{ 92}`
`(2x+96)/(3)=92`

Multiply bothside by 3

`2x\text{ + 96 =276}`

subtract 96 from bothside

`2x\text{ =180}`

Divide bothside by 2

`x=(180)/(2)`
`x=90`

substitute x =90 into z = 6+ x

z = 6 + 90 =96

The three test scores are;

90, 90, 96