Steven has 14 steel balls of equal weight. If he puts 9 of them in one pan of a pan balance and the rest along with a weight of 20 grams in the other pan, the pans balance each other. What is the weight of one steel ball?
Answer:
5 grams
Step-by-step explanation:
Let x represent the weight of each ball.
9 steel balls in one pan would then have a weight of 9x.
This leaves 14-9 = 5 balls for the other pan; they have a weight of 5x. Additionally we add 20 grams to this pan; this gives us 5x+20.
This gives us the equation
9x = 5x+20
Subtract 5x from each side:
9x-5x = 5x+20-5x
4x = 20
Divide both sides by 4:
4x/4 = 20/4
x = 5