Unit 3 Review- Addition/Subtraction

value of the sum

100

456+321=

777

200

539+232=

771

300

198+785=

983

400

978+549=

1,527

500

356+768=

1,124

find the difference

100

347-124=

223

200

468-248=

220

300

567-193=

374

400

550-253=

297

500

900-427=

473

rounding

100

What is 238 rounded to the nearest tens?

240

200

What is 485 rounded to the nearest hundreds? 

500

300

What is 750 rounded to the nearest tens and nearest hundreds?

nearest tens: 750

nearest hundreds: 800

400

What is 245 rounded to the nearest tens and nearest hundred?

nearest tens: 250

nearest hundreds: 200

500

What is 304 rounded to the nearest tens and nearest hundreds? 

nearest tens: 300

nearest hundreds: 300

write an equation

100

There are 50 pieces of candy in the jar. 20 pieces were jolly ranchers. 10 were starburst. The rest of the pieces were reeces. 

reeces= r

50-(10+20)=r

20+10+r=50

300

A box contains 120 markers. 6 students each take 2 markers. Letter m represents how many markers are left in the box.

120 - (6x2) = m

120 - (2x6) = m

solve it

100

A classroom has 30 desks. There are 15 students who show up up and then 12 more students show up to class. How many empty seats are there?

3 empty seats