Convert from Expanded Form - Up to Hundreds
π₯ The Explosion! What happens when a math problem is blown apart into giant pieces with plus signs in the middle? We squish it back together!
Do this: Read the concept below, then try the quiz or activity.
Concept
Some teachers like to write numbers in "Expanded Form". It sounds scary, but it's actually the easiest trick of all.
π― The Zipo Trick: "What number is 600 + 40 + 8?"
This is just 6 Hundreds, 4 Tens, and 8 Ones, but written with zeros! 1. Look at the FIRST digit of every number. (The 6, the 4, and the 8). 2. Grab them and squish them! 3. Answer: 648.
π― The Zero Trap Returns: "What number is 300 + 5?" 1. First digit of the Hundreds: 3. 2. First digit of the Tens: WAIT! There is no "40" or "80". The Tens are completely missing! You must write a 0. 3. First digit of the Ones: 5. 4. Answer: 305.
Try it
Squish the explosion!
Instructions: Look at the expanded addition sentence. Grab the front numbers and squish them together! Look out for missing tens!
Problem 1: 500 + 20 + 9 = ? * Grab the 5, the 2, and the 9. * Answer: ___
Problem 2: 800 + 70 + 0 = ? * Grab the 8, the 7, and the 0. * Answer: ___
Problem 3: 400 + 6 = ? * Watch out! There is no middle tens number! Add the 0! * Answer: ___
Problem 4: 100 + 10 + 1 = ? * Answer: ___