Use various strategies to and operations tosolve problems involving real numbers.
Decimal numbers are known as rationalnumbers. To understand decimals it isimportant to understand place value. (Poster)
Round the number 568.4587 to the nearest:
A. Tenth:
B. Hundredth:
C. Thousandth:
Round the following decimals to the nearesttenth.
1. 45.585. 4.543
2. 17.0416. 91.385
3. 5.2847. 25.483
4. 0.6188. 0.349
Round to the nearest hundredth.
1. 10.0495. 6.354
2. 0.7536. 5.729
3. 6.4327. 13.006
4. 32.8968. 31.456
Order the following decimals from least to greatest.
1.0.055, 0.05, 0.59, 0.05
2.0.7, 0.732, 0.74, 0.72
3.0.19, 0.09, 0.9, 0.1
When adding decimals, first arrange thenumbers in columns with the decimal pointsunder each other.
Ex. 0.9 + 2.5 + 63.17 =
Add. Be sure to write the decimal point in youranswer.
1.5.3 + 6.02 + 0.73
2.$3.75 + $18.90
3.1.25 + 4.1 + 10.007
When you subtract decimals, arrange thenumbers in columns with the decimal pointsunder each other.
Example: 5.25 – 4.7
Subtract. Be sure to write the decimal point inyour answer.
1.23.657 – 9.83
2.$40.99 – $9.99
3.15.789 – 6.32
4.102.5 – 1.079
Set up the problem as if you were multiplyingwhole numbers.
Multiply as if you were multiplying wholenumbers.
Count how many numbers are after thedecimal points in the problem.
Example: 15.2 x 3.5 =
Multiply.
1. 9.54 x 5.3
2. 5.72 x 6.3
3. 4.8 x 3.2
4. 5.003 x 0.009
Copy the problem as you would for wholenumbers. Copy the decimal point directlyabove in the place for the answer.
Example: 52.26 ÷ 6 =
Divide.
1. 42.75 ÷ 3
2. 74.16 ÷ 6
3. 152.25 ÷ 21
Copy the problem as you would for wholenumbers.
You cannot divide by a decimal number.
What you do to the outside – you must do tothe inside.
Example: 374.5 ÷ 0.07
Divide.
1. 0.676 ÷ 0.013
2. 70.32 ÷ 0.08
3. $54.60 ÷ 0.84
Write the following fractions as decimals.
A. C.
B. D.
1. Micah can have his bike fixed for$19.99, or he can buy the newpart for his bike and replace ithimself for $8.79. How muchwould he save by fixing his bikehimself?
2. Megan buys 5 boxes of cookiesfor $3.75 each. How much doesshe spend?
1. Which costs the most per ounce,60 oz of peanut butter for $5.40,28 oz for $2.24, or 16 oz for$1.76?
2. Which is the least per pound,5 lb of chicken for $9.45, 3 lbfor $5.97, or 1 lb for $2.05?
1. Troy bought a worm farm and decided toraise worms to make money. The worm farmcosts $110.00 initially and came with 200worms and 500 worm capsules, eachcontaining about 4 baby worms. He figureshe can sell the worms to bait shops for $1.25per dozen. How many dozen worms will hehave to sell to begin to make a profit? Wormseat table scraps, so there are no foodexpenses?
