Which of the following expressions correctly use mental math to find 4×59

? Select all that apply.

(1 point)
Responses

(4×60)−(4×1)
( 4 × 60 ) - ( 4 × 1 )

4×(50×9)
4 × ( 50 × 9 )

4+(50×9)
4 + ( 50 × 9 )

(4×50)+(4×9)
( 4 × 50 ) + ( 4 × 9 )

4+50+9

1 answer

To find 4 × 59 using mental math, we can use the distributive property, as well as other techniques. Let's evaluate each of the given expressions to see if they correctly compute 4 × 59:

  1. (4×60)−(4×1): This simplifies to 240 - 4 = 236, which is 4 × 59. (Correct)

  2. 4×(50×9): This simplifies to 4 × 450 = 1800, which is not 4 × 59. (Incorrect)

  3. 4+(50×9): This simplifies to 4 + 450 = 454, which is not 4 × 59. (Incorrect)

  4. (4×50)+(4×9): This simplifies to 200 + 36 = 236, which is 4 × 59. (Correct)

  5. 4+50+9: This simplifies to 4 + 50 + 9 = 63, which is not 4 × 59. (Incorrect)

Thus, the correct expressions that use mental math to find 4 × 59 are:

  • (4×60)−(4×1)
  • (4×50)+(4×9)