Q20 of 47 Page 172

By inserting parenthesis (that is brackets), you can get several values for 2 × 3 + 4 × 5. (For example ((2 × 3) + 5 is one way of inserting parenthesis.) How many such values are there?

The values are


(2 × 3) + 4 = 6 + 4 = 10


3 + ( 4 × 5) = 3 + 20 = 23


2 + (4 × 5) = 2 + 20 = 22


(2 × 3 + 4) × 5 = (6 + 4 ) × 5


= 10 × 5 = 50


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