Multiplying a decimal by a one-digit number

Find the product of two point five two and four. Try it first. Pause if you like. Multiply one place at a time, beginning with the hundredths. Keep each digit in its column. Two hundredths times four is eight hundredths. Write eight in the hundredths column. Five tenths times four is twenty tenths. Ten tenths make one whole, so twenty tenths make two ones. Carry two ones above the ones digit. No tenths remain. Keep the tenths position open for its zero. Two ones times four is eight ones. Add the two carried ones to get ten ones. Ten ones make one ten and zero ones. Write one in the tens column and zero in the ones column. Now write the zero in the reserved tenths column. The eight stays in the hundredths column. Put the decimal point directly under the original point. Four is a whole number, so the decimal places stay aligned. Two point five two times four equals ten point zero eight. Multiply each place and include any carry. The zero in the tenths keeps the eight in the hundredths.

Find the product of three point four six and seven. Try it first. Pause if you like. Begin with the hundredths again. This time, both decimal places will rename. Six hundredths times seven is forty-two hundredths. Forty-two hundredths is four tenths and two hundredths. Write two, and carry four tenths. Four tenths times seven is twenty-eight tenths. Add the four carried tenths to get thirty-two tenths. Thirty-two tenths is three ones and two tenths. Write two in the tenths column, and carry three ones. Three ones times seven is twenty-one ones. Add the three carried ones to get twenty-four ones. Twenty-four ones is two tens and four ones. Write both in their columns. Place the decimal point directly under the original point. The product still has hundredths. Three point four six times seven equals twenty-four point two two. Work from right to left. Rename ten lower-place units as one unit in the next place, and keep the decimal point aligned.