Question

Ramon was studying pond life in Doyle Park. In two hours, he counted four more frogs than turtles. The number of crayfish he counted was three more than twice the number of turtles. In total, he counted 54 turtles and crayfish. How many frogs were there?

Answer 1

frogs = 13

Explanation:

Lets denote

Turtle as t

Frog as f

Crayfish as c

Two hours has nothing to do with the answer, it is added just to confuse the student.

He counted four more frogs than turtles

t = 4 + f ----------- ( 1 )

Number of crayfish was three more than twice the number of turtles

c = 3 + 2 ( t ) ----- ( 2 )

Total, he counted 54 turtles and crayfish

t + c = 54 --------- ( 3 )

How many forgs

f = ?

From eq ( 3 )

c = 54 - t ----- ( 4 )

put c in eq ( 2 )

54 - t = 3 + 2 ( t )

54 - 3 = 2 ( t ) + t

51 = 3 ( t )

t = 17 -------- ( 5 )

put t in eq ( 1 )

17 = 4 + f

f = 17 - 4

f = 13 -----------( 6 )

For finding c put t = 17 in eq ( 4 )

c = 54 - 17

c = 37

To check if the answer is right, put values of t and c in eq 3

17 + 37 = 54

54 = 54 ----- L.H.S = R.H.S