64-3x8

=64-24

=40

Calculate the correct result again:

64-40÷8

=64-5

=59

The correct result is 59.

Extended data

Mathematical calculation skills:

1, extracting common factor

This method actually uses multiplication, division and distribution to extract the same factor, and the remaining items in the exam are often added and subtracted, and an integer will appear.

Pay attention to the extraction of the same factor.

For example:

0.92× 1.4 1+0.92×8.59

=0.92×( 1.4 1+8.59)

2. Borrowing method

When using this method, we need to pay attention to observation and find the law. We should also pay attention to "repayment". It is not difficult to "borrow" and "repay" again.

When we see that an integer like 998,999 or 1.98 is close to a very easy calculation, we often use the borrowing method.

For example:

9999+999+99+9

=(9999+ 1)+(999+ 1)+(99+ 1)+(9+ 1)-4