500
Spongebob enjoys hunting for jellyfish. Spongebob catches 337 jellyfish on the first day and 443 jellyfish on the second day. How many jellyfish does Spongebob catch altogether? Explain your reasoning.
What is I can solve this problem by breaking apart the addends into hundreds, tens, and ones. 300+400=700. 30+40=70 and 7+3=10. I can regroup the 10 ones as 1 ten to get 70+10=80. So, the sum is 700+80=780.