Mean, Average, you name it!

Algebra Level 3

If the average of p , q , r , p,q,r, and s s is − 3 -3 , then what is the average of 3 p − 2 q , 2 p − 3 s , 5 r + 8 s 3p-2q, 2p-3s, 5r+8s and 7 q − 28 7q- 28 ?

18 18 22 22 9 9 − 22 -22 − 18 -18 − 9 -9 − 27 -27

Hana Wehbi by Hana Wehbi , 51, USA

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Marta Reece
Jun 22, 2017

The second average is

1 4 × [ ( 3 p − 2 q ) + ( 2 p − 3 s ) + ( 5 r + 8 s ) + ( 7 q − 28 ) ] = 1 4 ( 5 p + 5 q + 5 r + 5 s − 28 ) = \dfrac14\times[(3p-2q)+(2p-3s)+(5r+8s)+(7q- 28)]=\dfrac14(5p+5q+5r+5s-28)=

5 × p + q + r + s 4 − 28 4 5\times\dfrac{p+q+r+s}{4}-\dfrac{28}4 = 5 ( − 3 ) − 7 = − 22 =5(-3)-7=\boxed{-22}

1 Helpful 0 Interesting 0 Brilliant 0 Confused

Thank you.

Hana Wehbi - 3 years, 11 months ago

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...