Question

write an expression that can be used to find 4 times 275 using mental math and properties of numbers.

Answer 1

Rough estimate:  4 times 300 = 1200

Properties of numbers:  4 times (300-25) = 4 times 300 - 4 times 25
                                                                   =         1200   - 100
                                                                   =               1100 (exact answer)

Answer 2

(200×4) + (70×4) + (5×4)