Question

The average of five numbers is 23. If the average of first two numbers is 21 and that of last two numbers is 19, what is the third number from starting?

Answer 1

Answer:

You can consider both first two numbers to be 21 and both last two numbers to be 19. Let’s also term the middle number as x, then let’s write down the equation for x and solve it.

(42 + 38 + x)/5 = 23

42 + 38 + x = 115

x = 115 - 42 - 38

x = 115 - 80

x = 35

Answer 2

Answer:

35

Step-by-step explanation:

let the sum of first two no be x+y

let the sum of last two no be a+b

let the third no be z

(x+y)/2=21

x+y=42  (1)

(a+b)/2=19

a+b=38 (2)

(x+y+a+b+z)/5=23

(42+z+38)/5=23

42+z+38=115

80+z=115

z=115-80

z=35

thank you