Cogito
Grade 4 Math · Chapter 6 · Lesson 6
Decimals and Money
A cent is one hundredth of a dollar.
10 problems · about 14 minutes · 4.NF.C.6, 4.MD.A.2
What this lesson teaches
The child uses decimal notation for money and solves money word problems.
- One cent is one hundredth of a dollar.
- Money is written to two decimal places.
- $0.05 and $0.50 are very different amounts.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
2 problemsReview — Adding Tenths and Hundredths: 7/10 + 15/100. How many hundredths?
Answer 85
Why 85/100, written 0.85.
Review — Comparing Decimals: Which is bigger, 0.9 or 0.89?
Answer 0.9.
Why 90 hundredths beats 89 hundredths.
Warm Up
Straightforward practice. Get the method working first.
4 problemsHow many cents is $0.35?
Answer 35
Why 35 cents.
What is one cent, as a fraction of a dollar?
Answer One hundredth.
Why One cent is 1/100 of a dollar.
How many cents is $0.08?
Answer 8
Why Eight hundredths.
How many cents is $0.80?
Answer 80
Why Eighty hundredths.
Build It Up
The same ideas with more to keep track of.
2 problemsHow many cents make one dollar?
Answer 100
Why A full grid.
Which is more, $0.09 or $0.9?
Answer $0.9, which is 90 cents.
Why Look at the tenths place.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
2 problemsThe Shop: A pen costs 45 cents. How many cents is $1 minus that?
Answer 55 cents
Why 55 cents, written $0.55.
The Total: 30 cents plus 25 cents. How many cents?
Answer 55 cents
Why 55 cents, written $0.55.