Franklin lent Darlene as much money as she already had, then she spent $10. The next day, Franklin lent her as much money as she now had and again, she spent $10. On the third day Franklin once again lent her as much money as she now had and she spent $10, leaving her broke. How much money did Darlene start with?
$8.75 You may have been tempted to guess $30 because $10 is spent three times, but that would mean she would have had $60 ($30 lent plus the $30 she already had), and $50 after spending $10. The rest of the numbers end up at higher than zero, so we know it has to be less than $30. Even starting at $10 leaves Darlene with $10 on the third day. Starting with $8.75 works out as follows.
I’m a sifter of a memorable shape, You can eat a variety of me, but I can be toxic, I can cause severe pain if you’re not careful, And the action I describe could hurt as well.
Kidneys filter your blood and are shaped like kidney beans, which you can eat. Red kidney beans contains high amounts of phytohemagglutinin (quite the word, eh?) and can be toxic if not soaked and boiled. Kidney stones can be extremely painful and if a kid knees you in the stones, that would also be unpleasant.
The problem works out to a set of three equations: b + c + d = 22 a + c + e = 22 a + b + c + d + e = 30
Solving for c = 14, leaving d = 8 – b and e = 8 – a. In other words, c must be 14, but the other two numbers just have to add up to 8. The requirement that they be unique rules out 4 + 4, so you’re left to choose from the following combations for b + d and a + e: 0 + 8 1 + 7 2 + 6 3 + 5