Question

In a class test, the average mark of Leena and meena is 80. The average of Meena and Reena is 86 and the average of Leena and Reena is 90. find the Meena's mark​

Answer 1

Answer:

let

Reena-R. Leena-L. Meena-M

first condition

( L+M )

80 = ————

2

160=(L+M). __________1

second condition

(M+R)

86= —————

2

172= (M+R). __________2

third condition

180=(L+R)

180 – L =R. ___________3

put this 3 in eqn 2

172=M + 180–L

L= M + 8. ___________4

put 4 in eqn 1

160 =L+M

160= (M+8 )+ M

160–8=2M

152=2M

76=M

meena's marks was 76

do you get?