If x is the average (arithmetic mean) of 4a and 26, y is the average of 5a and 36, and z is the aver

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06 Mar 2020 Arithmatic

If x is the average (arithmetic mean) of 4a and 26, y is the average of 5a and 36, and z is the average of 3a and 28, what is the average of x , y, and z in terms of a?

OPtion

1) a+5
2) 2a+5
3) a+10
4) a+15
5) 3a+5
6) 3a+10
7) 2a+15
8) 4a+5
9) 4a+!5
10) None of these

Solution

Since the average (arithmetic mean) of two numbers is equal to the sum of the two numbers divided by 2, the equations x= (4a+26)/2
y = (5a+36)/2 and
z = (3a+28)/2


The average of x, y, and z is given by (x+y+z)/3

Substituting the expressions in a for each variable (x, y, z) gives = ((4a+26)/2 + (5a+36)/2 + (3a+28)/2)/3 = (12a+90)/6 = 2a + 15

Correct Option: 7 Best Solution (2)

Mayank Kandoi   4 years AGO

Average of x,y,z = (4a+26+5a+36+3a+28)/2*3
= (12a+90)/6
= 2a+15

Like? Yes (1) | No   

SAYAN CHATTERJEE   4 years AGO

avg is (4a+26+5a+36+3a+28)/2/3= 2a+15.
Option 7.

Like? Yes | No (1)