A mother is currently twice as old as her daughter. 10 years ago, the mother was three times as old as her daughter. How old is the daughter today?
20 years old
Let D be the daughter's current age. Mother is 2D. 10 years ago, Mother was 2D - 10 and daughter was D - 10. Equation: 2D - 10 = 3(D - 10) => 2D - 10 = 3D - 30 => D = 20.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
More logic riddles
Five house numbers on a street are consecutive even numbers. If the sum of all five house numbers is 170, what is the largest house number?
A row goes: sled, sled, boot, sled, sled, boot, sled, sled. What comes next?
A shepherd needs to cross a river with a wolf, a goat, and a basket of cabbages using a small boat that can only carry the shepherd and one item at a time. However, the wolf cannot be left alone with the goat, and the goat cannot be left alone with the cabbages. To successfully cross the river while keeping everything safe, what is the absolute minimum number of one-way boat trips the shepherd must make from start to finish?
Two clocks are set to 12:00 Midnight. Clock A gains 2 minutes every hour. Clock B loses 3 minutes every hour. How many hours will pass before Clock A is exactly 1 hour ahead of Clock B?
A row goes: flag, flag, firework, flag, flag, firework, flag, flag. What comes next?
Three boxes are labeled 'Apples', 'Oranges', and 'Apples and Oranges', but all three labels are currently placed incorrectly on the wrong boxes. You are allowed to draw exactly one piece of fruit from only one box to fix all the labels. Which box do you choose?