Explain how to make these couculations mentaly a. 99+54 b.244-99

Use estimation

Step-by-step explanation:

A) 99 + 54

estimate that 99 is 100

estimate that 54 is 55

Add 100 and 55 together

100 + 55 = 155

Remember that you added 1 to 99 and 1 to 55

So you must subtract 2 from 155

155 - 2 = 153

Your answer is 153.

B) 244 - 99

estimate that 244 is 245

estimate that 99 is 100

Add 245 and 100 together

245 + 100 = 345

Remember that you added 1 to 245 and 1 to 99

So you must subtract 2 from 345

345 - 2 = 343

Your answer is 343.

Remember that you are doing all of this in your head!

I hope this helps!

- sincerelynini

this might get deleted, sorry. it has to be an actual question. if you really wanted to give someone free points, ask a question like "why does the sky look blue, and the sun is yellow to our eyes? "

step-by-step explanation:

the camry sales+accord sale=828,000. to make it so the two numbers are 18 thousand apart and still equal 828,000, you first need to find out what half of 828,000 is. 828,000/2=414,000. for the two numbers to equal 828,000, you have to add the same amount as you subtract from the middle. in this case, the number is 9,000 because it's half of 18,000. to equal 828,000, you have to add 9,000 to 414,000 for the camry and subtract 9,000 from 414,000 for the accord. 414,000+9,000=423,000.

414,000-9,000=405,000.

423,000+405,000=828,000.

423,000-405,000=18,

hope it