Answer:
Number of rocks and fossils collected by you is 1 and 24 respectively
Number of rocks and fossils collected by your friend is 3 and 12 respectively
Step-by-step explanation:
Let the number of Rocks you collect be x
Let the number of Fossils you collect be y
Then the total number pf objects you collected will be
x + y = 25
x = 25 - y------------------------------(1)
Your friend collects three times as many rocks and half as many fossils as you.
This can be written as
3x + y (1/2) = 15
3x + (y/2) = 15-------------------(2)
Substituting (1) in (2)
3(25 - y) + (y/2) = 15
75 - 3y + (y/2) = 15
Grouping the like terms we get,
75 - 15 = 3y = (y/2)
60 = ( 6y - y /2)
60 x 2 = 6y -y
120 = 5y
y = 120/5
y = 24
Substituting y value in equation(1) we get
x = 25 - 24
x= 1
y= 24
Friends collects 3 times rock
so collects 3x =3(1) = 3rocks
Also he collects half as many fossils
That is
y/2 = 24/2 = 12 fossils
Hope this help you! :)
