Question

In Aunt Melly's attics there are also spiders and ants, the total of 136 legs and 20 heads. If a spider has 8 legs and an ant has 6 legs, how many spiders and how many ants are there?

Answer 1

Spiders=8

Ants=12

Explanation:

Spider(s)=8 legs

Ants(a)=6 legs

Total legs=136

Total heads=20

8s+6a=136 (1)

s+a=20 (2)

From (2)

s=20-a

Substitute 20-a into (1)

8s+6a=136

8(20-a)+6a=136

160-8a+6a=136

160-2a=136

-2a=136-160

-2a=-24

a= -24/-2

a=12

Substitute a=12 into (2)

s+a=20

s+12=20

s=20-12

s=8