Question

a+a+a=60.....a+b+b=30......c+b+c=9........a+d+c=42....a+b×c=?​

Answer 1

Answer:

30

Step-by-step explanation:

a+a+a=60

3a=60

a=20

a+b+b=30

a+2b=30

But a=20

∴20+2b=30

2b=30-20

b=5

c+b+c=9

2c+b=9

But b=5

∴ 2c+5=9

2c=4

c=2

Also, a+d+c=42

20+d+2=42

d=42-22

d=20

Clearly, a+d×c

= 20+5×2

= 20+10

=30