Add and Subtract Units, Tens and Hundreds | Year 3 Maths Resources

KS2 SATs Flash Cards

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What you need to know

Things to remember:

• To make addition and subtraction easier we can split our numbers into hundreds, tens and units.

Let’s see how we can split our numbers into hundreds, tens, and units to make addition easier.

$$24+2=20+4+2=20+6=26$$

$$313+5= 300+10+3+5=300+10+8=318$$

We can do the same for tens and hundreds:

$$356+40=300+50+6+40=300+50+40+6=300+90+6=396$$

$$219+300=200+10+9+300=200+300+10+9=500+10+9=519$$

Just because, sometimes when we add our units will become tens, and tens will be come hundreds!

$$356+60= 300+50+6+60=300+50+60+6=300+110+6=416$$

We can do subtractions in the exact same way!

$$218 - 4 = 200 + 10 + 8 - 4=200+10+4=214$$

$$256 - 20 = 200 + 50 +6-20=200 + 50 - 20 +6 = 200+30+6=236$$

$$299-100=200+90+9-100=200-100+90+9=100+90+9=199$$

Sometimes we need to be careful with subtractions as well. If the number we are taking away is bigger, we need to “borrow 1” from the bigger number.

$$532-70=500 + 30 - 70 + 2 = 400 + 130-70 +2=400+60+2=462$$

Example Questions

425+300=400 + 20 + 5 + 300 = 400+300+20+5=700+20+5=725

265-90=200+60-90+5=100+160-90+5=100+70+5=175

Times Table Flash Cards

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• All of the KS2 times tables are covered
• Engaging and fun maths cards