Your brain, of course.
It depends on your computational skills.
compatible numbers
Break it up into two separate problems. First 4X25=100, which is easy enough. Then 27X100=2700.
dont know about associative property but this one is easy in your head. 4x25=100x27=2700
No, but if you practice you can learn to do it and it gets easier. Start of by learning (by rote) your times tables and when adding up do so in 10s.
Compatible Numbers numbers that are easy to compute mentally are called
Compatible number
benchmark numbers
It depends on your computational skills.
compatible numbers
Break it up into two separate problems. First 4X25=100, which is easy enough. Then 27X100=2700.
dont know about associative property but this one is easy in your head. 4x25=100x27=2700
No, but if you practice you can learn to do it and it gets easier. Start of by learning (by rote) your times tables and when adding up do so in 10s.
easy to divide mentally
partial qoutient division is an easy way to do division
easy well not really
Compatible numbers can easily be divided mentally.