Approximating the measures of quantities particularly length, weightmass and volume.pptx

ALGEBRA-MATHEMATICS 7

1. 7 + 3 = - 2 + 7 = 6 + 5 = - 1 + 5 = - 5 +(-8) = 10 5 11 4 -13

2. - 6 + 1 = - 3+(-6) = - 5+ 0= - 1 + 1 = 3 +(-6) = -5 -9 -5 -3

3. Approximating the measures of quantities particularly length, weight/mass and volume Mathematics 7

4. Objectives: Approximates the measures of quantities particularly length, weight/mass, volume, time, angle and temperature and rate ( M7ME-IIa-3 ). Describe what it means to measure A pproximate lengths, weight/mass and volume Appreciate the importance of estimation/ approximation and measurements in everyday life

5. Important Terms to Remember: Measurement- the process or the result of determining the ratio of a physical quantity such as length, time, temperature, and others to a unit of measurement such as meter, second, or degree Celsius . Palm – the width of one’s hand excluding the thumb Hand span – the distance from the tip of the thumb to the tip of the little finger of one’s hand with fingers spread apart. Forearm length – the length of one’s forearm: the distance from the elbow to the tip of the middle finger.

6. History of Measurement One of the earliest tools that human beings invented was the unit of measurement. In olden times, people needed measurement to determine how long or wide things are; things they needed to build their houses or make their clothes. Later, units of measurement were used in trade and commerce. In the 3rd century BC Egypt, people used their body parts to determine measurements of things; the same body parts that you used to measure the assigned things to you.

7. History of Measurement The forearm length was called a cubit. The hand span was considered a half cubit while the palm was considered 1/6 of a cubit. The Egyptians came up with these units to be more accurate in measuring different lengths. These units of measurement are called non-standard units of measurement which later on evolved into what is now the inch, foot and yard, basic units of length in the English system of measurement.

8. English System of measurement The inch, foot and yard are said to be based on the cubit. They are the basic units of length of the English System of Measurement, which also includes units for mass, volume, time, temperature and angle. Since the inch and foot are both units of length, each can be converted into the other. Here are the conversion factors, as you may recall from previous lessons: 1 foot = 12 inches 1 yard = 3 feet For long distances, the mile is used: 1 mile = 1,760 yards = 5,280 feet

9. METRIC System of measurement The English System of Measurement was widely used until the 1800s and the 1900s when the Metric System of Measurement started to gain ground and became the most used system of measurement worldwide. First described by Belgian Mathematician Simon Stevin in his booklet, De Thiende (The Art of Tenths) and proposed by English philosopher, John Wilkins, the Metric System of Measurement was first adopted by France in 1799. In 1875, the General Conference on Weights and Measures ( Conférence générale des poids et mesures or CGPM) was tasked to define the different measurements. By 1960, CGPM released the International System of Units (SI) which is now being used by majority of the countries with the biggest exception being the United States of America.

10. Here are the common prefixes used in the Metric System arranged from smallest to largest: Nano (n) Micro ( μ ) Milli (m) Centi (c) Deci (d) Deka (da) Hecto (h) Kilo (k) Mega (M) Giga (G) Tera (T )

11. The fundamental unit of length in the Metric System is meter (m) The following are examples of the measuring devices used to measure length.

12. • To measure small quantities, like thickness of a book, length of a paper clip, or the size of a microchip, use millimeters (mm) • To measure quantities like the length of the fork, a pencil, or a book, use centimeters (cm). • To measure longer lengths like the length of flagpole, dimensions of a piece of land, use meters (m). • To measure the distance between towns, use kilometers (km).

13. Mass and weight are two different measurements, but weight is often used in our daily lives. Mass refers to the amount of matter an object has while weight is the gravitational force acting on an object . The fundamental unit of weight in the metric system is gram (g). To measure a small amount of weight, milligram(mg) is used, while to measure large amount of weight, kilogram(kg) is used.

14. Volume is the amount of space an object contains or occupies. The volume of a container is considered to be the capacity of the container. This is measured by the number of cubic units or the amount of fluid it can contain and not the amount of space the container occupies. The fundamental unit of volume in the metric system is Liter (L). Small volumes like liquid medicine are measured in milliliters(mL) . Large volumes like water in tanks, reservoirs, or swimming pools are measured in cubic meters ( ) . The following are examples of the measuring devices used to measure small amount of volume.  

15. Exercise 1 Choose which of the given device is the most appropriate in measuring the given item. Encircle the letter that corresponds to the correct answer. 1. A device used to determine the weight of a 5-peso coin. ruler B . platform balance C . measuring cups 2. It is used to determine the length of a ball pen. tape measure B . weighing scale C. ruler

16. 3 . It is a device used in measuring the amount of flour for baking a cake. measuring cups B . meter stick C. ruler 4. A device used to measure your weight. platform balance B . digital weighing scale C . triple beam balance 5. It is used to measure your waistline. A. Ruler B . meter stick C . tape measure

17. Exercise 2 Encircle the most reasonable measure listed for each illustrated item. 1. A . 50 g B . 50 mg C . 50 kg 2. A . 14 mm B . 14 cm C . 14 m

18. Bacolod City Cadiz City 3 . A . 1 L B . 1 mL C . 10 mL A . 100 cm B . 54 km C . 33 m

19. A . 1 kg B . 50 g C . 50 kg

20. English System of measurement Metric System of measurement Length Foot ( ft ) , yard, inch (in), miles (mi) Length Meters (m) Weight/ mass Pound ( lb ), ounce s ( oz ) Weight/ mass Grams (g) Volume Cubic feet Cubic inches Quart Pint Gallon (gal) Volume Cubic meter Liter (L) English System of measurement Metric System of measurement Length Foot ( ft ) , yard, inch (in), miles (mi) Length Meters (m) Weight/ mass Pound ( lb ), ounce s ( oz ) Weight/ mass Grams (g)

21. Tell what metric unit of measure is appropriate in measuring the following : 1. The height of your mother 2 . The length of your ballpen 3 . The distance of your home from your school 4 . The length of a book The thickness of this book Weight of 5 peso coin Weight of a person Weight of 1 sack of rice A bottle of medicine A bottle of Soda