grade 7 mathematics second quarter activity sheet no. 3
type of activity: concept notes
activity title: quantities and units used
learning competency: approximates the measures of quantities particularly length, weight/mass, volume, time, angle and temperature and rate. (m7me - lla - 3)
learning targets: 1. identify the commonly used units of measurement and corresponding unit.
2. use appropriate instrument to measure these quantities.
references: 21st century mathematics 7 by villano et al.
pages: 200 - 204
concept notes:
the table below shows the different quantities and their base units.
| quantity | base unit | other units | measuring instrument |
|--|--|--|--|
| length | meter (m) | millimeter (mm), centimeter (cm), kilometer (km) | meter stick, tape measure, ruler |
| weight/mass | kilogram (kg) | milligram (mg), gram (g), ton | weighing scale, bathroom scale |
| volume | cubic meter (m³) | cubic centimeter (cm³), liter (l), milliliter (ml) | graduated cylinder, measuring cup |
| time | second (s) | hour, day, month, year | stopwatch, sundial, watch |
| angle | degree (°) | - | protractor |
| temperature | degree celsius (°c) | degree fahrenheit (°f) | thermometer |
| rate | meter per second (m/s) | kilometer per hour | speedometer |
example:
in order to design the blackboard in a classroom, tina needs to measure the length and width of the board.
what appropriate measuring tool will she use?
what will be the best unit to express the result, and the degree of accuracy?
solution:
tina can use a tape measure or meter stick to measure the length and the width of the board.
she can choose meter or m to represent the measure of the length and the width of the board.
exercises:
a. choose the appropriate metric unit to measure each item. underline the appropriate answer.
1. typical room height (meter centimeter millimeter)
2. time to finish 100 m dash (minute hour second)
3. weight of a melon (milligram kilogram gram)
4. the speed of a bullet (meter/second kilometer/hour meter/hour)
5. a cup of coffee (liter milliliter)
b. underline the most appropriate instrument to measure the following.
1. width of a textbook (ruler micrometer tape measure)
2. diameter of a p1 coin (micrometer ruler tape measure)
3. the weight of a boxer (platform balance bathroom scale triple - beam balance)
4. time to finish a test (sundial stopwatch hourglass)
5. degree of hotness needed to bake a cake (oven thermometer clinical thermometer)

Question

Accepted Answer

# Explanation:
## Step1: Recall metric units for length
For a typical room height, meter is a suitable unit as centimeter and millimeter are too small. So the answer for 1. is meter.
## Step2: Recall time - unit for a 100 m dash
The time to finish a 100 m dash is measured in seconds. So the answer for 2. is second.
## Step3: Recall mass - unit for a melon
The weight of a melon is measured in kilograms as milligram is too small and gram is usually for smaller objects. So the answer for 3. is kilogram.
## Step4: Recall speed - unit for a bullet
The speed of a bullet is measured in meters per second or other speed - related units. Kilometer per hour is also a speed unit but not as common for bullet speed as m/s. So the answer for 4. is meter/second.
## Step5: Recall volume - unit for a cup of coffee
The volume of a cup of coffee is measured in milliliters or liters. Since a cup is a relatively small volume, milliliter is more appropriate. So the answer for 5. is milliliter.
## Step6: Recall instrument for width of a textbook
The most appropriate instrument to measure the width of a textbook is a ruler as it is suitable for measuring relatively small - length objects. So the answer for B1. is ruler.
## Step7: Recall instrument for diameter of a coin
The diameter of a P1 coin is very small, and a micrometer is the most appropriate instrument for such a small measurement. So the answer for B2. is micrometer.
## Step8: Recall instrument for weight of a boxer
The weight of a boxer is measured using a platform balance as it can measure relatively large masses. So the answer for B3. is platform balance.
## Step9: Recall instrument for time to finish a test
The time to finish a test is measured using a stopwatch as it can accurately measure short - to medium - length time intervals. So the answer for B4. is stopwatch.
## Step10: Recall instrument for temperature to bake a cake
The degree of hotness needed to bake a cake is measured using an oven thermometer as it is designed to measure the temperature inside an oven. So the answer for B5. is oven thermometer.

# Answer:
A.
1. meter
2. second
3. kilogram
4. meter/second
5. milliliter
B.
1. ruler
2. micrometer
3. platform balance
4. stopwatch
5. oven thermometer

Sovi.AI - AI Math Tutor

QUESTION IMAGE

Question

Explanation:

Step1: Recall metric units for length

Step2: Recall time - unit for a 100 m dash

Step3: Recall mass - unit for a melon

Step4: Recall speed - unit for a bullet

Step5: Recall volume - unit for a cup of coffee

Step6: Recall instrument for width of a textbook

Step7: Recall instrument for diameter of a coin

Step8: Recall instrument for weight of a boxer

Step9: Recall instrument for time to finish a test

Step10: Recall instrument for temperature to bake a cake

Answer:

quantity	base unit	other units	measuring instrument
weight/mass	kilogram (kg)	milligram (mg), gram (g), ton	weighing scale, bathroom scale
volume	cubic meter (m³)	cubic centimeter (cm³), liter (l), milliliter (ml)	graduated cylinder, measuring cup
time	second (s)	hour, day, month, year	stopwatch, sundial, watch
angle	degree (°)	-	protractor
temperature	degree celsius (°c)	degree fahrenheit (°f)	thermometer
rate	meter per second (m/s)	kilometer per hour	speedometer