Question

Question # 1 The average of x, y , z and 40 is 10. What is the average of x, y and z.


Q#2 The area of the circle is 16π. The length of the diameter of the circle is


Q#3 Maria's test scores were 96, 97, 86, 98 and 92. What would he need on his next test to have an average of 94?

Answer 1

1)Average of x,y,z and 40 is 10=> x+y+z+40/4 =10=>
x+y+z+40 =4(10)=40=> x+y+z=0. So average of x,y and z is 0/3 =0.
2) Area of the circle is 16π=πr^2 => 16=r^2 => r=4 . length of the diameter of the circle is 2(4)=8.
3) Average of 96,97,86,98,92 and x is 94 =>
96+97+86+98+92+x/6 =92=> 193+184+92+x=6(92)
=552=> 387+92+x=552=> 479+x =552=> x=552-479
= 73. He needs 73 on the next test to have an average of 94.