Operations with decimals

Addition
EX:    1
          .47
        +.36
          .83
Adding decimal game
http://www.math-play.com/baseball-math-adding-decimals/adding-decimals.html

Subtraction
EX:        51
              .625
            -.238
             .387

Multiplication

Multiplying by powers of 10
to multiply a decimal by a power of 10, move the decimal point one place to the right for each power of 10.
EX:  10x.165= 10 x (1/10+6/100+5/1000) = 10/10 + 60/100 + 50/1000
                                                                            1     +    6/10  +   5/100
                                                                                      =1.65

Division
Measurement concept:  repeatedly measuring off or subtracting one amount from another
 Sharing concept:  the shaded part of a decimal square is divided into four equal parts

.8/2=.4

there are .4 in each group









Dividing powers of 10
Move the decimal point one place to the left for each power of 10
EX:  .37/10= (3/10 + 7/100) x 1/10 = 3/100+7/1000 = .037