Question 20 of 24intermediate🔧 ApplyFill in the Blanks2 marks

Using only reasoning of how terms change their values, fill the blanks to make the expressions on either side of the equality (=) equal. (a) 423 + ___ = 419 + ___ (b) 207 - 68 = 210 - ___

(a)
Answer

The two blanks must differ by 4. Example: 423 + 10 = 419 + 14

(b)
Answer

71

Explanation

(a) 423 is 4 more than 419, so the right blank must be 4 more than the left blank. (b) 207 - 68 = 139. 210 - 71 = 139. Since 210 is 3 more than 207, the subtrahend must be 3 more than 68.