Lesson # 7

Decimals written as money !

When doing operations with decimals…

• Think about MONEY !

How much money is $0.05

a) 5 cents

b) 5 dollars

c) Half a cent

d) Or half a dollar ?

If you said…

$0.05 is …half a dollar…or half a cent…or 5 bucks……then…

I’m sorry…

• You are

• WR

O

N

G

!!!!!!!!!!

$0.05 is equal to 5 cents.

Another example…

• $0.025 is equal to…

A) A quarter

B) Two and a half cents

C) Twenty five cents

D) Two dollars and fifty cents.

If you said that $0.025 is equal to

B) Two and a half cents, then you are right!

So…

• When adding, subtracting, multiplying or dividing …

• Numbers with DECIMALS….

Think about…

Cash

MONEY

An example of adding…

$0.015 + 0.015 = ?

$0.015 = one and a half cents

• Soooooooooo

0.015 + 0.015 equals…

• One and a half cents PLUS one and a half cents…

• ( 0.03) Three Cents !

An example of subtracting…

• $1.25 – $0.05 = ?

Think…

• $1.25 equals one dollar and twenty five cents…

• Subtract…

• $0.05 (a nickel)

• Therefore $1.25 - $0.05 = $1.2 (One dollar and twenty cents)

An example of Multiplying…

0.12 x 2.0 = ?

Convert the “friendliest” number into groups and the other to

MONEY!

0.12 x 2.0

• Make the 0.12 the money (12 cents)

• Make the 2.0 the number of groups

That means you have …

• Two groups of 12 cents…

• Which is 24 cents ( 0.24) !

An example of dividing…

• $0.35 ÷ 0.05 = ?

Think…

0.35 (35 cents) ÷ 0.05(5 cents)

How many times would…

• Five cents fit into 35 cents?

Seven ?

Right !

Lets get ready for 12 practice questions !

• That’s right “12” ,

• 3 add,• 3 subtract,• 3 multiply and• 3 divide.

Question # 1

0.1 + 0.01 = ?

Question # 2

0.25 – 0.2 = ?

Question # 3

0.5 x 3.0 = ?

Question # 4

0.35 ÷ 0.05 = ?

Question # 5

4.75 + 0.2 = ?

Question # 6

1.5 – 0.75 = ?

Question # 7

0.08 x 5.0 =

Question # 8

1.25 ÷ 0.25 = ?

Question # 9

0.025 + 0.25 = ?

Question # 10

1.1 – 0.03 = ?

Question # 11

25.0 x 0.01 = ?

Question # 12

2.25 ÷ 0.25 = ?

And now the answers…

• Get Ready!

Question # 1

0.1 + 0.01 =

0.11

Question # 2

0.25 – 0.2 =

0.05

Question # 3

0.5 x 3.0 =

1.5

Question # 4

0.35 ÷ 0.05 =

7

Question # 5

4.75 + 0.2 =

4.95

Question # 6

1.5 – 0.75 =

0.75

Question # 7

0.08 x 5.0 =

0.4

Question # 8

1.25 ÷ 0.25 =

5

Question # 9

0.025 + 0.25 =

0.275

Question # 10

1.1 – 0.03 =

1.07

Question # 11

25.0 x 0.01 =

0.25

Question # 12

2.25 ÷ 0.25 =

9

The

END !