MAT-144 · Mathematical Reasoning
Topic 07 · Taxes & Stocks
Rounding decimals
Round to a target place value: whole, tenth, hundredth. Same rule every time.
01
Worked Example Video
Every step of Rounding decimals explained on video. Pause anywhere; the embed scrolls independently of the page.
YOUTUBE
02
What This Looks Like on ALEKS
ALEKS randomizes the numbers each attempt, but the question shape stays the same. Here are two example versions you might see.
Rounding decimals
Round 6.7 to the nearest whole number.
6.7 ≈
✓
Right — the tenths digit is 7, which is 5 or more, so we round up. 6.7 becomes 7.
✗
Not quite. Check the tenths digit (7) — since 7 is 5 or more, we round up. So 6.7 rounds to 7.
Rounding decimals
Round 0.78 to the nearest tenth.
0.78 ≈
✓
Right — the hundredths digit is 8, which is 5 or more, so we round the tenths digit (7) up to 8. Answer: 0.8.
✗
Not quite. Check the hundredths digit (8) — since 8 is 5 or more, we round the tenths digit (7) up to 8. Answer: 0.8.
Heads up: Your ALEKS version will use different numbers. The numbers in the practice below are different too — that way you're exercising the move, not memorizing one answer.
03
The Rule
Deciding digit is 5 or more
round up
Deciding digit is 4 or less
round down
Find the rounding place, then look at the digit one step to its right. That digit decides.
Common slip
Students who miss this question almost always look at the wrong digit. The fix: identify the rounding place first (the place you're rounding to), then look one step to its right. That right-neighbor digit is the only one that matters for the rule.
04
Practice — Step by Step
Practice this problem step by step
Round 4.83 to the nearest tenth.
Find the rounding place
Click the digit in the tenths place of 4.83.
In 4.83, the digit right after the decimal point sits in the tenths place.
✓
Yes — the 8 is in the tenths place, one step to the right of the decimal.
✗
Not quite. The tenths place is directly to the right of the decimal point.
Look one place to the right
Now click the digit immediately to the right of the tenths place — the deciding digit.
The hundredths place is two steps to the right of the decimal point.
✓
Right — the 3 in the hundredths place is our decider. It tells us which way to round.
✗
Not quite. The deciding digit is one step further to the right after the tenths place.
Apply the rule
The deciding digit is 3. Since 3 is less than 5, which way do we round?
The rule: 5 or more, round up. 4 or less, round down. Our deciding digit is 3.
✓
Right — 3 is less than 5, so we round down. The tenths digit stays at 8; the hundredths digit drops away.
✗
Not quite — try again.
Write the answer
You've done all the work. Type the rounded value.
4.83 ≈
Round down means the tenths digit (8) stays the same, and the hundredths digit (3) disappears.
✓
Perfect. 4.83 rounded to the nearest tenth is 4.8. The hundredths digit (3) drops; the tenths digit (8) stays because we rounded down.
✗
Not quite. Round-down means the tenths digit (8) stays put, and the hundredths digit (3) goes away — leaving 4.8.
🎉
You walked the rounding move end to end.
Same three steps every time: find the rounding place, look one digit to its right, apply the rule. ALEKS will give you a different number — maybe rounding to the hundredth instead of tenth — but the move is identical.