Lesson 1 Part 1
Question 1 Kenji goes to a technical school.His school has 627 male students and 215 female students. How many students does his school have in total?
The total number of students in Kenji’s school is the sum of the number of male students and the number of female students. If you add the two numbers together, you can find the total number of students in Kenji’s school. Therefore, Kenji’s school has 842 students, because 627 plus 215 equals 842.
The total number of students in Kenji’s school is the sum of the number of male students and the number of female students. If you add the two numbers together, you can find the total number of students in Kenji’s school. Therefore, Kenji’s school has 842 students, because 627 plus 215 equals 842.
Lesson 1 Part 1-1
Kenji goes to a technical school.
Lesson 1 Part 1-2
His school has 627 male students and 215 female students.
Lesson 1 Part 1-3
How many students does his school have in total?
Lesson 1 Part 1-4
The total number of students in Kenji’s school is the sum of the number of male students and the number of female students.
Lesson 1 Part 1-5
If you add the two numbers together, you can find the total number of students in Kenji’s school.
Lesson 1 Part 1-6
Therefore, Kenji’s school has 842 students, because 627 plus 215 equals 842.
Lesson 1 Part 2
Question 2 Japan’s population in 1990 was approximately 123.6 million, and it increased to 127.3 million in 2013. How much did the population increase in these 23 years?
If you want to know the answer, you need to find the difference between two numbers. You can find the difference between two numbers by subtracting one number from the other number.
Therefore, subtracting 123.6 million from 127.3 million shows that the Japanese population increased by 3.7 million between 1990 and 2013.
If you want to know the answer, you need to find the difference between two numbers. You can find the difference between two numbers by subtracting one number from the other number.
Therefore, subtracting 123.6 million from 127.3 million shows that the Japanese population increased by 3.7 million between 1990 and 2013.
Lesson 1 Part 2-1
Japan’s population in 1990 was approximately 123.6 million, and it increased to 127.3 million in 2013.
Lesson 1 Part 2-2
How much did the population increase in these 23 years?
Lesson 1 Part 2-3
If you want to know the answer, you need to find the difference between two numbers.
Lesson 1 Part 2-4
You can find the difference between two numbers by subtracting one number from the other number.
Lesson 1 Part 2-5
Therefore, subtracting 123.6 million from 127.3 million shows that the Japanese population increased by 3.7 million between 1990 and 2013.
Lesson 1 Part 3
Question 3 Here is a cardboard box to contain new pencils. The cardboard box contains two dozen small boxes and each box contains a dozen pencils. How many pencils does the cardboard box contain?
To find the total number of pencils, you multiply the number of small boxes by the number of pencils in each small box. There are 24 small boxes, and 12 pencils are contained in each small box. Therefore, the total number of pencils is 288, because 24 times 12 equals 288.
In expressions of multiplication like 2 × 3 or a × b, each number or letter is called a factor. The result of a multiplication is called the product. In an expression a × b = c, a and b are factors, and c is the product of a and b.
To find the total number of pencils, you multiply the number of small boxes by the number of pencils in each small box. There are 24 small boxes, and 12 pencils are contained in each small box. Therefore, the total number of pencils is 288, because 24 times 12 equals 288.
In expressions of multiplication like 2 × 3 or a × b, each number or letter is called a factor. The result of a multiplication is called the product. In an expression a × b = c, a and b are factors, and c is the product of a and b.
Lesson 1 Part 3-1
Here is a cardboard box to contain new pencils.
Lesson 1 Part 3-2
The cardboard box contains two dozen small boxes and each box contains a dozen pencils.
Lesson 1 Part 3-3
How many pencils does the cardboard box contain?
Lesson 1 Part 3-4
To find the total number of pencils, you multiply the number of small boxes by the number of pencils in each small box.
Lesson 1 Part 3-5
There are 24 small boxes, and 12 pencils are contained in each small box.
Lesson 1 Part 3-6
Therefore, the total number of pencils is 288.
Lesson 1 Part 3-7
Because 24 times 12 equals 288.
Lesson 1 Part 3-8
In expressions of multiplication like 2 × 3 or a × b, each number or letter is called a factor.
Lesson 1 Part 3-9
The result of a multiplication is called the product.
Lesson 1 Part 3-10
In an expression a × b = c, a and b are factors, and c is the product of a and b.
Lesson 1 Part 4
Question 4 If a car travels 200 kilometers in 4 hours, what is the average speed of the car?
The average speed of a moving object is the distance it travels in a unit of time. To find the average speed of the car, you divide the distance the car travels by the time it takes. As the car travels 200 kilometers in 4 hours, the average speed of the car is 50 kilometers per hour, because 200 divided by 4 equals 50.
A fraction is an expression of division. For example, you can use three fifths to show the result of three divided by five. In a fraction, the number written above the bar is the numerator, and the number written below the bar is the denominator.
The average speed of a moving object is the distance it travels in a unit of time. To find the average speed of the car, you divide the distance the car travels by the time it takes. As the car travels 200 kilometers in 4 hours, the average speed of the car is 50 kilometers per hour, because 200 divided by 4 equals 50.
A fraction is an expression of division. For example, you can use three fifths to show the result of three divided by five. In a fraction, the number written above the bar is the numerator, and the number written below the bar is the denominator.
Lesson 1 Part 4-1
If a car travels 200 kilometers in 4 hours, what is the average speed of the car?
Lesson 1 Part 4-2
The average speed of a moving object is the distance it travels in a unit of time.
Lesson 1 Part 4-3
To find the average speed of the car, you divide the distance the car travels by the time it takes.
Lesson 1 Part 4-4
As the car travels 200 kilometers in 4 hours, the average speed of the car is 50 kilometers per hour.
Lesson 1 Part 4-5
Because 200 divided by 4 equals 50.
Lesson 1 Part 4-6
A fraction is an expression of division.
Lesson 1 Part 4-7
For example, you can use three fifths to show the result of three divided by five.
Lesson 1 Part 4-8
In a fraction, the number written above the bar is the numerator.
Lesson 1 Part 4-9
And the number written below the bar is the denominator.