2.3× 12=27.6

Analysis: When calculating the decimal multiplication, first turn the decimal into an integer, then expand 2.3 times 10 to 23, and then calculate it as an integer.

23×2=46; 23× 10=230.46 plus 230 equals 27. Finally, it is observed that there is a decimal place in the factor of 2.3× 12, so 276 counts one place from right to left and points the decimal point. Thus, the correct product is 27.6.

Vertical type means that each transition number is changed by the last transition number, and then the single digits of the last transition number are multiplied by 2. If carry is needed, proceed to 1, then increase the unit number by ten digits, and so on, and add a new operand to the unit number.

Extended data:

Matters needing attention in vertical decimal multiplication

1, with vertical columns, is mantissa alignment of factors.

2. When the column is vertical, for the convenience of calculation, factors with more digits are generally put on it.

3. If there are integer 10000 factors, the first digits of the two factors from the right are non-zero-aligned, and then the corresponding number of zeros is filled in the number.

If there is 0 at the end of the number, count the decimal point first, and then go to 0.

5. If there are not enough decimal places, you need to add 0 in front.