Math 2 Lesson: Kilometers
1.1. Knowledge to remember
– The unit of measurement for the length of the kilometer, the symbol and magnitude of the kilometer, the relationship of the kilometer to the metric unit.
– Addition, subtraction and related math problems.
– The application of the kilometer unit in life.
1.2. Math forms
Form 1: Converting units of measurement
I remember how to convert units
Form 2: Perform addition and subtraction with numbers with length units
For numbers with the same unit of measure, add or subtract the numbers and keep the unit of measure in the result.
Form 3: Calculate the length of the bend line
To calculate the length of a bend, we calculate the sum of the lengths of the straight segments of that bend.
1.3. Solving Textbook Exercises
1km = …m ….m = 1km
1m =…dm …dm = 1m
1m = …cm …cm = 1dm
Convert length units and fill in the blanks with the appropriate number.
1km = 1000m; 1m = 10dm = 100cm.
1km = 1000m 1000m = 1km
1m = 10dm 10dm = 1m
1m = 100cm 10cm = 1dm
Look at the figure and answer the following questions:
a) How many kilometers is the distance from A to B?
b) How many kilometers is the distance from B to D (through C)?
c) How many kilometers is the distance from C to A (through B)?
– Look at the figure and find the lengths of the straight lines of the bend.
– Calculate the total length of the related line segments.
a) The distance from A to B is 23km long.
b) The distance from B to D (through C) is 90km long.
(42km + 48km = 90km)
c) The distance from C to A (through B) is 65km long (Because 42km + 23km=65km).
Indicate the appropriate measurement (according to the form):
Read the data recorded on the map and then fill in the table.
a) Cao Bang and Lang Son, which is farther from Hanoi?
b) Lang Son and Hai Phong, which is closer to Hanoi?
c) Which distance is longer: Hanoi-Vinh or Vinh-Hue?
d) Which distance is shorter: Ho Chi Minh City – Can Tho or Ho Chi Minh City – Ca Mau?
Based on the data entered in lesson 3; Compare and answer the questions.
a) Because 285km > 169km, Cao Bang is farther from Hanoi than Lang Son.
b) Because 169km > 102km, Hai Phong is closer to Hanoi than Lang Son.
c) Since 368km > 308km, the Vinh-Hue distance is longer than the Hanoi-Vinh distance.
d) Because 174km < 354km, the distance between Ho Chi Minh City and Can Tho is shorter than the distance between Ho Chi Minh City and Ca Mau.