Answer:
old 36 cents
new 45 cents
So isolate the variable on the left side by dividing both sides by 4/5:
4/5*5/4n = 5/4*9
on the left 4/5 and 5/4 cancel each other out and you end up with:
n = 5/4*9 = (5*9)/4 = 45/4 = 11 1/4 or 11.25
The price of a packet of salt goes up to 9 cents.The old price is four-fifths of the new price.Find the old and new prices. [Hint:let the old price be n cents.So the new price is n+9 cents\