Maths
posted by help needed .
A spider has 8 legs, a dragonfly has 6 legs. Given a number of spiders and
dragonflies altogether have 420 legs, number of spiders are 3 times the
number of dragonflies, the number of spiders are?

8s+6d=420
3D= s
8s+6(s/3)=420
10s=420
s= 42
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