An antique collector purchases an old pocket watch for $60, sells it to an enthusiast for $70, purchases the same watch back for $80, and finally sells it again for $90. Across these transactions, what was the collector's total overall profit?
$20
Treat each trade independently: the first transaction produces $70 - $60 = $10 profit, and the second produces $90 - $80 = $10 profit. Total profit equals $10 + $10 = $20.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
More math riddles
I am a polygon with fewer sides than a pentagon, but more sides than a triangle. My interior angles add up to 360 degrees. What shape am I?
If yesterday was the day before Wednesday, what day of the week is tomorrow?
A wall clock strikes once at 1 o'clock, twice at 2 o'clock, and so on. How many total strikes does it make in a single 24-hour day?
12 green hats are shared equally among 4 friends. How many green hats does each friend get?
Eli has 8 pencils and finds 4 more. How many pencils does Eli have now?
If two painters can paint two identical walls in two hours, how many painters are needed to paint 18 identical walls in 18 hours?