math3rd grade
posted by elaine on .
Write the +/ family for:500, 1100, 1600.
What do i do?
1100+500=1600
500+1100=1600
16001100=500
1600500=1100
Is that correct? Please help.Thank you.

Hi elaine,
Yup, that is all correct. Well done! 
Thank you

explain how 3 group partial sums work

needs help in math. I don't know what this is all about but I would to get her some help. Thanks her mom ( Julene )

Oops, missed out some equations
such as
500 + 1600,
sorry about that 
together with 1100 + 1600, 1100  500, and I'm not sure if you also want to include those with negative answers..

give three numbers that make each statement true.
1. 12+(?) is greater than 20. 
Explain your thinking. Use the digits 1, 3, 4, 5, 7, and 9 to write two money amounts that you can subtract by trading 1 dollar for 10 dimes. Then solve.