contestada

A biologist was sitting near a pond and noticed a large number of dragonflies. He also saw both frogs and fish trying to eat the
dragonflies. He counted a total of 89 fish, frogs, and dragonflies. He noticed that there were four times as many dragonflies as fish and
that the frogs were five more than twice the number of fish

Respuesta :

89 /3

frogs = 29.6

fish =  29.6

dragonflies =  29.6

all of them equal 89

debmc7
Guessing you need to know how many of each animal there are

a = fish = 12
b = frog = 29
c = dragonflies = 48

a + b + c = 89

c = 4a (four times as many dragonflies as fish)
b = 2a + 5 (frogs were five more than twice the number of fish)

Then substitute for b and c in the big equation:

a + (2a + 5) + 4a = 89
Combine like terms:
7a + 5 = 89
Subtract 5 from both sides:
7a = 84
Divide both sides by 7:
a = 12

Now use this to solve for b and c

c = 4(12) = 48

b = 2(12) + 5 = 24 + 5 = 29

Please let me know if you have any questions.

Otras preguntas