Math 6

1. “Solving word
problems involving
direct proportion”
6th
grade

2. Multiply or divide the following mentally
1. 25 x 5 =
2. 30 x 10 =
3. 900 ÷ 3 =
4. 180 ÷ 90 =
5. 6 x 2 =
125
300
300
2
12

3. Review:
a . _N_ = 5_
40 8
b. _3_ = _N_
5 30
c. _8_ = _4_
18 N
Find the missing term in a proportion and
check your answer
d. 15_ = _N_
30 2
e. 10_ = 5_
N 2

4. What do you do on weekends?
Do you know that you can earn
extra money during weekends
when you are industrious or
hardworking?
by making “Nipa Shingles”

5. Marlou and Gerry sell Nipa Shingles on weekends to earn extra money for their students.
For every 3 Nipa Shingles that marlou sells, Gerry sells 5. If marlou sold 15 Nipa Shingles,
How many did Gerry sell?
Steps in solving a problem:
1. Analyze the problem
2. What is being asked?
3. What are given?
_3_ _15_
5 N
4. Illustrate the problem.
Marlou =
Gerry =
Presentation
=

6. 5. Set up a proportion
Marlou - _3_ _15_
Gerry - 5 N = 25
 The proportion is called Direct Proportion. The
quantities change in the same direction.
 As the number of Nipa Shingles that Marlou sells
increases, the number of Nipa Shingles that Gerry
sells also increases.
=
3xN = 5X15
3N = 75
3N = 75
3 3
N = 25
Check:
3 = 15
5 25
3x25 = 5x15
75 = 75

7. Activity 1(Teacher & Pupils)
The sign on the store windows says “
Magazine for sale, Buy 3, take 2 “ How
many magazines must I buy if I want to
take 10 magazines for free?
3 magazines = N magazines
2 free magazines 10 free magazines
2xN = 3x10 3 = 15
2N = 30 2 10
2N=30 3x10 = 2x15
2 2 30 = 30
N=15 .

8. Activity 2 (by Pair)
At the School canteen:
a) 3 pieces of pad paper cost 45 cents
21 pieces of pad paper cost ______
b) 4 colored pencils cost 25.
₱
12 colored pencils cost _______
c) 2 boiled bananas cost 3.50
₱
10 boiled bananas cost _______

9. Individual Activity: Solve for the Following
1) Bea can bake 40 boxes of brownies in 4 hours. How many
boxes of brownies can she bake in 6 hours?
2) A chef can prepare 10 dishes in an hour. How long it will
take for him to prepare 300 dishes for a party?
3) Sanny can deliver 3 pieces of lechon in 6 minutes. If If 18
pieces of lehon are ordered in different locations. How
many minutes will it take him to deliver it then?

10. Generalization
1. Analyze the problem
2. What is being asked
3. Illustrate the problem
4. Set up a proportion
5. Find the missing terms of proportion
6. Check your answer using cross product rule
How can we solve word problems involving direct
proportion?

11. Read and analyze each word problem then solve
for the answer.
a) One serving of a dish can feed 5 pupils. How
many servings of the dish are needed to serve
35 people?
b) Three liters of gasoline can be used to travel
at a distance of 48 kilometers. How far can 5
liters go?
Application

12. 1. A tree cast a shadow of 12 meters when a 5- meter pole casts a
shadow of 4 meter s. How tall is the tree?
2. At the rate of 3 items for ₱100, Hown much will 12 items costs?
3. A car travels 72 km on 8 liters of gasoline. At the same rate,
about How far can it travel an 11 liters of gasoline?
4. The ratio of duck eggs to chicken eggs in an egg store is 2:7 . If
there are 312 duck eggs in the store, How many chicken eggs
are there?
5. The ratio of men to women working for a construction
company is 10:3 if there are 21 women in the construction
company, How many men are there?
Evaluation

13. Assignment:
Write a proportion for each problems. Then find the
missing term.
a) The ratio of 2 numbers is 3.5. The larger number
is 30. What is the smaller number?
b)There are 3 teachers to 125 pupils during the
school program. How many teachers were there if
there were 3,500 pupils?