LT

Test: Addition and subtraction within 20

Dynamic addition, subtraction, missing-number and short word-problem tasks within 20.

Question qty: 6
Duration in minutes: 8
Start »

Time left: 00:00:00

Sample questions

  • Which number fits? a − __ = r.
  • Calculate: a + b.
  • Which subtraction equation is correct for a and b?
  • Which addition equation is correct for a and b?
  • a pages were read, then b more. How many pages were read in total?
  • There were a passengers on a bus. b got off. How many remained?

Addition and subtraction within 20

When calculating within 20, it helps to split a number into ten and ones. Count forward to add and backward to subtract, first reaching the nearest ten when useful.

Word problems

Words such as “more”, “altogether” and “in total” usually suggest addition, while “got off”, “gave away” and “left” suggest subtraction. Find a missing addend by subtracting the known addend from the sum. Check with the inverse operation and ensure the result answers the question.