Decimal Multiplication

fraction form

100

2.3  x  1.8

414/100 = 4  14/100 = 4.14

200

 2.38  x  1.8   

4284/1000 = 4  284/1000 = 4.284

300

 A kitchen measures 3.7 meters by 4.2 meters.

What is the area?

1554/100 = 15  54/100 = 15.54 square meters

must include the correct unit to earn points. 

unit form

100

2.3  x   0.9 

207 hundredths = 2.07

200

2.37  x  0.9    

 2,133 thousandths = 2.133

300

 Sarah buys 1.2 pounds of cheese. If each pound cost $3.70, how much will she pay?

4440 thousandths or 444 hundredths = 4.44

She will pay $4.44.

 

short cut

100

6.6  x   2.8     

 1848.  move decimal point 2 place values to the left

= 18.48

200

 3.2  x  1.2

384.     move the decimal 2 place values to the left.

= 3.84

300

Kevin has a length of rope that measures 1.3 meters. He used 3 tenths of the rope to tie a knot. How many meters of rope are in the knot? 

 1.3  x  0.3  =  39.  move the decimal 2 place values to the left.

=0.39 meters of rope are in the knot

your choice

100

 3.3  x  0.14

.462

200

6.06  x  2.8

16.968

300

 Grace had 3.3 kg of flour. She used 7/10 of it to bake a wedding cake for her sister. How much flour did grace use for the cake?

3.3  x  0.7 = 2.31

Grace used 2.31 kg of flour for the wedding cake.