Find the following values without a calculator.
Give your answers in this manner. (Eg 1, 2, 3, 4)
- 900 + 20 + _____ = 923
- 1000 + _____ + 70 = 1870
- _____ + 70 + 8 = 6078
- 60000 + _____ + 7 = 62407
(a)
900 + 20 + _____ = 923
920 + _____ = 923
923 - 920 = 3
(b)
1000 + _____ + 70 = 1870
1070+ _____ = 1870
1870 - 1070 = 800
(c)
_____ + 70 + 8 = 6078
_____ + 78 = 6078
6078 - 78 = 6000
(d)
60000 + _____ + 7 = 62407
60007 + _____ = 62407
62407 - 60007 = 2400
Answer(s): 3, 800, 6000, 2400