Question

pl tell the correct answer ​

Answer 1

Answer:

5, 28, 24 respectively

Given that

Sum Of Data : 10 * 17 + 30 * (5a + 3) + 50 * 32 + 70 * (7a-11) + 90 * 19

Number Of Data : 17 + 5a + 3 + 32 + 7a - 11 + 19

Evaluate respectively.

Sum Of Data

→ 10 * {17 + 3 * (5a + 3) + 5 * 32 + 7 * (7a - 11)+9 * 19}

→ 10 * (17 + 15a + 9 + 160 + 49a - 77 + 171 )

→ 10 * (64a + 280)

→ 640a + 2800

Number Of Data

→ 5a + 7a + 17 + 3 + 32 - 11 + 19

→ 12a + 60

The given mean is 50.

Also, mean : $\frac{640a+2800}{12a+60}$

→ $\frac{640a+2800}{12a+60}=50$

→ $\frac{160a+700}{3a+15} =50$

→ $50(3a+15)=160a+700$

→ $150a+750=160a+700$

→ $10a=50$ Isolate a in left hand side.

∴ $a=5$

Frequency of 30 : $5a+3=28$

Frequency of 70 : $7a-11=24$