Third Grade Math Question, I'm Terrible At Math.. Can You Help?

I went to the store and bought 6 shirts, but I need a total of eleven.
You would use this to figure out what you need in a situation
hope this helps!

49 + ___ = 78

If I had to fill in the blank, I'd probably do it like this.
49 + 1 makes 50, and 28 more make 78. Since 1 + 28 is 29, the blank gets filled with 29 and the complete sentence is

49 + 29 = 78

A third grader might not jump to 28, but might add by 10s to get 60, 70, and then 8 more to get 78. If one were counting out change, one might count
49 + 1 makes 50, 8 more make 58, and 20 makes 78. The change is 1+8+20 = 29. A certain amount of planning and short-term memory are involved.
_____
Fundamentally, this is algebra. Somehow people forget how to do it from 3rd grade to 7th grade, or they get shaken by the use of a variable instead of a blank. 49+x = 78, x = 78-49 = 29.

Well actually lucky for you I am excellent at math it is my best subject. You can email me anytime with a math question.

49 + _____ =  78     The question is asking for a missing addend.  Addends are the numbers added together to get an answer.  You have to turn your subtraction sentence around to make an addition sentence; therefore using the greatest number as your answer in an addition sentence.  You already have one addend (49), you just need to find the missing addend (??) to equal 78.  That part I'll let you figure out on your own so you can say you found the answer.

Well. Whatever adds to 49 to get 78 is the answer. So, 49 + 29 = 78, so 29 is the missing addend.

I will teach you how to do percent of a number                       thank you see ya.

Lets start with 70 of 90, now the of means I need to multiply.


First divide 70 by 100 70                     _70___= 0.7                          
                                                             100

second multiply.                        _70__ = 0.7 x 90 =  63                                               
                                                    100