Mixed Math: Add & Subtract Money
π Red Light vs. Green Light (Money Edition!). Did you earn the money, or did you drop the money in a storm drain?
Do this: Read the concept below, then try the quiz or activity.
Concept
The ultimate test of fluency. You must read the sign and instantly switch the rules in your brain.
π― The Universal Money Rules: 1. Green Light (+): Stack the dots! Start right. Make number bigger. Carry (+1) if 10 or more. Drop the dot! 2. Red Light (-): Stack the dots! Start right. Make number smaller. Knock next door & borrow if top number is stuck. Drop the dot!
If you add a Subtraction problem, your money will be completely wrong.
Try it
Do not cross the streams!
Instructions: Check the sign (+ or -). Pick the right universe of rules! Drop the dot!
Problem 1: $0.65 + $0.28 ------- * Sign: PLUS! (Add them!). 5+8=13. Carry the 1. * Answer: $_.___
Problem 2: $0.81 - $0.34 ------- * Sign: MINUS! (Take away!). 4 is bigger than 1. Go next door to the 8! * Answer: $_.___
Problem 3: $0.40 - $0.25 ------- * Sign: MINUS! (0 is stuck! Go next door!). * Answer: $_.___
Problem 4: $0.50 + $0.50 ------- * Sign: PLUS! (0+0=0. 5+5=10. Write the whole 10!). * Answer: $_.___