Placing the decimal point in division
Grade 4 students learn to place the decimal point correctly in division problems involving money in Saxon Math Intermediate 4. The rule is simple: the decimal point in the answer goes directly above the decimal point in the dividend. When dividing 54.80 dollars by 4, place the decimal in the quotient first, then divide as with whole numbers to get 13.70 dollars. Forgetting this step turns a 13.70 dollar answer into 1370 — a huge error. This Chapter 8 skill ensures accuracy when calculating unit prices, splitting costs, and dividing money amounts.
Key Concepts
When dividing numbers involving money, the process is the same as with whole numbers, with one important rule for the decimal point. The decimal point in the answer is placed directly above the decimal point inside the division box. This ensures that the value of the answer correctly represents dollars and cents without any extra calculation.
The total cost of four identical books is 9.20 dollars. To find the cost of each book, divide: $9.20 \div 4 = 2.30$ dollars. To split 7.95 dollars among 5 friends, you calculate: $7.95 \div 5 = 1.59$ dollars per person. If eight movie tickets cost 50.00 dollars, each ticket costs: $50.00 \div 8 = 6.25$ dollars.
When dividing money, the decimal point is super polite—it never cuts in line! It just floats straight up from the number you are dividing into its final spot in the answer. This simple trick keeps your dollars and cents perfectly aligned, so you do not accidentally turn ten dollars into ten cents. Easy peasy!
Common Questions
Where does the decimal point go when dividing money?
The decimal point in the quotient is placed directly above the decimal point in the dividend inside the division box. This should be done before performing any division steps.
How do you divide a money amount like 54.80 by 4?
Set up 54.80 divided by 4. Place the decimal point in the answer above the decimal in 54.80. Then divide: 5 divided by 4 is 1 with remainder 1, bring down 4 to get 14, divide 14 by 4 is 3 remainder 2, bring down 8 to get 28, divide 28 by 4 is 7, bring down 0, divide 0 by 4 is 0. Answer: 13.70 dollars.
What is the most common mistake when dividing decimals?
Forgetting to place the decimal point before dividing. If you solve 54.80 divided by 4 and write 1370 instead of 13.70, you have made an error worth a factor of 100.
Why must you place the decimal before dividing?
Placing the decimal first acts as a guide to keep all subsequent digits in their correct place value positions. Without it, the quotient digits land in the wrong columns.
What Saxon Math chapter teaches placing the decimal in division?
Placing the decimal point in division is covered in Saxon Math Intermediate 4, Chapter 8 (Lessons 71-80), as part of dividing money amounts and decimals.