Question
Find the following values without a calculator.
  1. 10 - 1 = _____
  2. 200 - 74 = _____
  3. 70 - 40 = _____
  4. 800 - 31 = _____
1 m
(a)

Click button first when a symbol is required. X

(b)

Click button first when a symbol is required. X

(c)

Click button first when a symbol is required. X

(d)

Click button first when a symbol is required. X

Find the following values without a calculator.
  1. 10 - 1 = _____
  2. 200 - 74 = _____
  3. 70 - 40 = _____
  4. 800 - 31 = _____