(2) When building a road, the ratio of the repaired length to the total length of the road is 5: 1 1, and the ratio of the repaired length to the unrepaired length is (5): (6). The repaired length is (5) of the unrepaired length, and the unrepaired length accounts for (65438).
2. There are 42 students in class 6 (1), 43 students in class 6 (2) and 45 students in class 6 (3) in Sunshine Primary School. In the tree planting activities on Arbor Day, the school assigned the task of planting 260 trees to three classes according to the number of classes. How many trees should be planted in each class?
The total number of students is 42+43+45= 130 (person)
Therefore, 1 class planted 260× 65438+42=84 trees out of 30 trees.
Class two plants trees for 30 minutes, 260× 65438+43=86 (plants).
Tree planting in Class Three takes 30 minutes (260× 65438+45=90).
The apples shipped from the store are 40 kilograms more than oranges. As we all know, the weight ratio of apples to oranges is 7: 3. How many kilograms of oranges are shipped out of the store?
Suppose the orange is 1, then the apple is 7/3.
Apples are 40 kilograms heavier than oranges.
So the orange is: 40 ÷ (7/3- 1) = 40 ÷ 4/3 = 30 (Jin).
4. The total length of a cuboid wood is 192 cm, and the ratio of length to width is 3: 1: 4. What is the volume of this cuboid wood?
Solution length+width+height = 192÷4=48 (cm)
Length: 48× (3+1+4) 3 = 48× 83 =18 (cm)
Width: 48×(3+ 1+4) copies 1=48×8 copies 1=6 (cm).
Height: 48×(3+ 1+4) 4=48×8 4=24 (cm).
Volume: 18×6×24=2592 (cubic centimeter)
A bus and a truck leave from two places 450 kilometers apart at the same time. It is known that the speed of passenger cars is 40 kilometers per hour, and the speed of passenger cars and trucks is 4∶5. How many hours after the two cars left?
Unloading speed is 40÷5 = 50 (km/h).
450÷(40+50)=450÷90=5 (hours) ..................................................... meeting time.
6. The school allocated 536 books to each class in proportion to the number of students in three classes in grade six. There are 45 students in Class One, 42 students in Class Two and 47 students in Class Three. How many books should each of the three classes get?
Three classes 45+42+47= 134 (person).
Class one got the book: 45% of 536× 134 =180 (volume).
Books assigned to Class Two: 536× 65438+42/034 = 168 (Ben).
Books are divided into three categories: 536× 65438+47/034 = 188 (Ben).
7. Enclose a rectangular vegetable field with a 56-meter-long fence with an aspect ratio of 4: 3. How many square meters is the area of this vegetable field?
Solution length+width =56÷2=28 (m)
Length: 28×(4+3) 4=28×7 4= 16 (m)
Width: 28×(4+3) 3=28×7 3= 12 (m)
Area: 16× 12= 192 (square meter).
8.( 1) Draw a rectangle with an area of18cm2 and an aspect ratio of 2: 1.
(2) Draw a rectangle with a circumference of 20 cm and an aspect ratio of 3: 2.
Solution (1) Length× width =2× width squared = 18
So, the square of the width =9.
Therefore, the width =3 (cm) and the length is 6 cm.
(2) Length+width =20÷2= 10 (cm)
Length:10× (3+2) 3 =10× 53 = 6 (cm)
Width:10× (3+2) 2 =10× 52 = 4 (cm).