Math Grade 4Mrs. Ennis

Standard Units of Measurement

Lesson Thirty-One

1. What is the sum of 250, 3, and 3,459?

2. 26,459 – 19,878 = G

3. Find the product of 8, 6, and 0.

4. J x 600 = 5400

5. 36 divided by 6

6. One half of 12

7. It is 3:00 now. What time was it 40 minutes ago?

8. Round 63,596 to the nearest thousand

9. The basketball game started at 11:00a.m. It lasted for 3 hours and 45 minutes. What time did it finish?

10. Zachary earns $5.00 per hour for working at the pet store. If he works five and a half hours, how much will he earn?

Conversions Using Standard Units of Measurement

Measurement

You are making a measurement when you

¨ Check you weight

¨ Read your watch

¨ Take your temperature

¨ Weigh a cantaloupe

Standards of Measurement

When we measure, we use a measuring tool to compare some dimension of an object to a standard.

Some Tools for Measurement

Measuring Time

Minutes:

3 Units of Measurement for Time:

Seconds:

there are 60 seconds in a minute

Hours:

there are 3600 Seconds in one hour

there are 60 minutes in an hour

there are 24 hours in an day

So how would we find out how many minutes are in 3 hours?

We would convert the hours to minutes.

3 x 60hours

minutes in each hour

= 180

minutes in 3 hours

In any conversion, when going from a smaller unit to a larger unit, always divide.

When going from a larger unit to a smaller unit, always multiply.

So how would we find out how many minutes are in 540 seconds?We would convert the seconds to minutes.

540 ÷ 60second

s seconds in each minute

= 9

minutes in 540 seconds

So how would we find out how many seconds are in a half hour?We would convert the minutes to seconds.

30 x 60minutes in a half hour

seconds in each minute

= 1800

seconds in a half hour

So how would we find out how many hours are in 660 minutes?We would convert the minutes to hours.

660 ÷ 60minute

s minutes in each hour

= 11

hours in 660 minutes

So how would we find out how many seconds are in 2 hours?

First we would convert the hours to minutes.

2 x 60hours

minutes in each hour

= 120

minutes in 2 hours

How many seconds are in 2 hours?

Then we would convert the minutes to seconds.

120 x 60minutes

seconds in each minute

= 7200

minutes in 2 hours

You try some:

300 minutes = _______ hours

7 hours = _______ minutes

40 minutes = _______ seconds

240 seconds = _______ minutes

5 hours = _______ seconds

5420 240

0 418000

Measuring Length

Feet:

3 Units of Measurement for Length:

Inches:there are 12 inches in a foot

Yards:

there are 36 inches in a yard

there are 3 feet in a yard

= 3 feet

How long is an inch?

A quarteris aboutan inch

wide 1 inch

How long is a foot?

About thelength of

a clipboard

1 foot

How long is a yard?

About thewidth ofa door

1 yard

In any conversion, when going from a smaller unit to a larger unit, always divide.

When going from a larger unit to a smaller unit, always multiply.

So how would we find out how many feet are in a 8 yards?

We would convert the yards to feet.3 x 8

Feet in one yard yards

= 24 ft

Feet in 8 yards

So how would we find out how many inches are in 6 feet?

We would convert the feet to inches.12 x 6

inches in one foot feet

= 72 in

inches in 6 feet

How many yards are in 27 feet?

We would convert the feet to yards.

27 ÷ 3feet

feet in each yard

= 9 yd

yards in 27 feet

How many inches are in 10 yards?

First we would convert the yards to feet.

10 x 3yards

feet in each yard

= 30 ft

feet in 10 yards

How many inches are in 10 yards?

Then we would convert the feet to inches.

30 x 12feet

inches in each foot

= 360 in

inches in 10 yards

36 feet = _______ yd

4 yd = _______ ft

60 in = _______ ft

120 ft = _______ yd

12 ft = _______ in

7 yd = _______ ft

Try these on your own:

4812

540

14484

Measuring Weight

Pounds:

3 Units of Measurement for Weight:

Ounces:

there are 16 ounces in a pound

Tons:

there are 2000 pounds in a ton

= 2000 pounds

In any conversion, when going from a smaller unit to a larger unit, always divide.

When going from a larger unit to a smaller unit, always multiply.

How many ounces are in 3 pounds?

We would convert the pounds to ounces.

3 x 16pounds ounces in

a pound

= 48

ounces in 3 lbs

How many pounds are in 160 ounces?

We would convert the ounces to pounds.

160 ÷ 16ounces

ounces in a pound

= 10

pounds in 160 oz

How many pounds are in 6 tons?

We would convert the tons to pounds.

6 x 2000tonspounds in a ton

= 12000pounds in 6 tons

How many ounces are in 2 tons?

First, we would convert the tons to pounds.2 x 2000tonspounds in a ton

= 4000pounds in 2 tons

How many ounces are in 2 tons?

Then, we would convert the pounds to ounces.4000 x

16pounds ounces in

a pound

= 64000ounces in 2 tons

32 oz = _______ lb

4 lb = _______ oz

5 tons = _______ lb

120 ft = _______ yd

12 ft = _______ in

7 yd = _______ ft

Try these on your own:

642

1000040

14484

Online Practice

Ounces and Pounds

Animal Weigh In

Inches to Feet

Hours and Minutes

Math Fun:Kim's uncle sends her a box of books each month. A box with 2 books costs 95 cents to mail; a box with 5 books costs $1.85. A box with 1 book costs 65 cents, one with 4 books costs $1.55; and a box of 3 books cost $1.25. How much did it cost him to mail a box of 6 books? How much would it have cost him to mail all 52 books at once?

Answer:

Each extra book cost 30 cents more. So six books cost $1.85 (for 5 books) + $0.30, or $2.15. All 52 books at once would have cost 65 cents for the first book and 51 x $0.30, or $15.30 for the rest. $15.30 +$0.65 = $15.95 for all 52 books.

http://mathlearnnc.sharpschool.com/UserFiles/Servers/Server_4507209/File/Instructional%20Resources/G4WW1-4.pdf

Resources:

http://math.pppst.com/measurement.html

http://www.bbc.co.uk/education/mathsfile/shockwave/games/animal.html

http://www.aaastudy.com/mea6_hx1.htm

http://www.sheppardsoftware.com/mathgames/measurement/MeasurementOunces.htm

http://www.sheppardsoftware.com/mathgames/measurement/MeasurementInches.htm