Buzz
Solving Math Grade 3 exercises on pages 86, 87 Workbook Volume 2
Solving exercises on pages 86, 87 of Math 3 Workbook Volume 2, book Connecting Knowledge with Life:
Vietnamese Currency
Activity
1. Solve Exercise 1 Page 86 Math Grade 3 Workbook
Problem: Which piggy bank contains the most money?
Guidance: Calculate the total amount of money in each piggy bank and find out which piggy bank contains the most money.
Answer:
- The pink piggy bank contains all: 10,000 + 20,000 + 20,000 = 50,000 (dong).
- The green piggy bank contains 100,000 dong.
- The purple piggy bank contains 50,000 dong.
So, the green piggy bank contains the most money.
2. Solve Exercise 2 Page 86 Math Grade 3 Workbook
Problem: Mom went to the market and spent 3,000 dong on lemons and 2,000 dong on onions. Mom gave the saleswoman 10,000 dong. Choose ways the saleswoman can give back the change to mom.
Guidance:
Step 1: Calculate the amount of money mom spent (total price of buying lemons and onions).
Step 2: Calculate the amount of change the saleswoman gives back to mom (subtract the total amount spent on lemons and onions from 10,000 dong).
Answer:
The amount of money mom spent is 3,000 + 2,000 = 5,000 (dong).
The amount of change the saleswoman gives back to mom is 10,000 - 5,000 = 5,000 (dong).
- Observing the picture, we have:
+ A: 5,000 dong.
+ B: 1,000 dong + 2,000 dong + 2,000 dong = 5,000 dong.
+ C: 2,000 dong + 2,000 dong + 2,000 dong = 6,000 dong.
So, the saleswoman can use method A or B to give back the change to mom.
3. Solve Exercise 3 Page 86 Math Grade 3 Workbook
Problem: When buying each item below, we need to pay a bill as shown. Find the price of each item, knowing:
- The price of the light bulb is the lowest;
- The price of the book is the highest;
- The price of the robot is higher than the price of the comb.
Guidance: Compare the prices of the items and then answer the question.
Answer:
- The price of the light bulb is the lowest. Therefore, the light bulb costs 10,000 dong.
- The price of the book is the highest. Therefore, the book costs 100,000 dong.
Practice
1. Solve Exercise 1 Page 87 Math Grade 3 Workbook
Problem: Find the price of each item: corn, carrot, cucumber.
Guidance: Observe the picture and calculate the price of each item.
Answer:
Observing the picture, we see:
- Corn costs 5,000 dong.
- Corn and carrot together cost 8,000 dong. So, the carrot costs:
8,000 dong - 5,000 dong = 3,000 dong.
- Corn, carrot, and cucumber together cost 10,000 dong.
So, the cucumber costs: 10,000 dong - 8,000 dong = 2,000 dong.
The corn riddle: How much for one corn? Lan bought one corn at the beginning of the corn season for 5,000 dong. Mid-season, with the same amount, she bought two corns. a) Mid-season, the price for one corn is? dong. b) The price for one corn at the beginning of the season compared to mid-season is? dong.
a) Mid-season, the price for one corn is 5,000 dong divided by 2 = 2,500 dong. b) The price for one corn at the beginning of the season compared to mid-season is: 5,000 dong - 2,500 dong = 2,500 dong.
a) Mid-season, the price for one corn is 5,000 dong divided by 2 = 2,500 dong. b) The price for one corn at the beginning of the season compared to mid-season is: 5,000 dong - 2,500 dong = 2,500 dong.
a) Mid-season, the price for one corn is 5,000 dong divided by 2 = 2,500 dong. b) The price for one corn at the beginning of the season compared to mid-season is: 5,000 dong - 2,500 dong = 2,500 dong.
At the school fair organized by the institution, Nam and Mai prepared lemonade to sell and support the charity fund. Below is the amount spent on purchasing the ingredients for making lemonade.
a) How much money do Nam and Mai need to buy the mentioned ingredients?
b) Nam and Mai sold lemonade for 80,000 dong. How much money do they have left after subtracting the cost of the ingredients?
a) Total amount needed to buy ingredients = amount spent on water + amount spent on sugar + amount spent on lemons.
b) Remaining amount of money = Amount earned from sales - cost of ingredients.
Following the calculations:
a) Total cost of ingredients = 25,000 dong + 15,000 dong + 20,000 dong = 60,000 dong.
b) Remaining amount = 80,000 dong - 60,000 dong = 20,000 dong.
Answers:
a) Nam and Mai need the amount to buy ingredients:
20,000 + 14,000 + 10,000 = 44,000 (dong)
b) After subtracting the cost of the ingredients, they have:
80,000 - 44,000 = 36,000 (dong)
Answer: a) 44,000 dong
b) 36,000 dong
4. Solve Exercise 4 Page 87 Mathematics Grade 3
Problem: Number?
Guidance for Solution: Choose an appropriate number of bills so that the total value of the bills equals the given number.
Answer:
Through the solution manual for exercises on pages 86, 87 of Mathematics 3 Workbook 2, Connecting knowledge with life, Mytour hopes that students can study well, solve exercises easily, and most importantly, absorb a lot of knowledge.
