15×48=720

Analysis: First calculate15× 8 =120; Calculate 15× 40 = 600, and add 120 and 600 to get the result.

Vertical points of two-digit multiplied by two-digit sequence:

1, the last bit is aligned.

2. Multiply the digits of the lower multiplier with the digits of the upper multiplier, and the digits of the product are aligned with the digits of the lower multiplier.

3. Multiply the ten digits of the multiplier below by the two digits above, and the digits of the product are aligned with the ten digits of the multiplier below.

4. Add the products calculated twice.

Extended data:

Law of integer multiplication:?

1, starting from the right, multiply the first factor by the number on each bit of the second factor, and the end of the number will be aligned with which bit of the second factor and on which bit of the factor; ?

2. Then add up the numbers multiplied by several times. ?

3. Multiply with 0 at the end of the integer: you can multiply the number before 0 first, then see how many zeros are at the end of each factor, and add a few zeros at the end of the multiplied number.