Answer:
132600
Step-by-step explanation:
I was always taught like this, and this should be the best estimate:
28 x 4417 --> 30 * 4420 --> 132600
Some other possible estimates with simpler values:
30 * 4400 --> 132000
30 * 4500 --> 135000
30 * 4000 --> 120000
I am not sure but I did this in my head and then I did it on the calculator and it was 20
