Fraction Problems

This section demonstrates how to solve practical problems involving fractions.

Example: Rachel needs to determine how many packs of butter to buy for 80 cupcakes, where each cupcake requires 2/25 of a pack.

The solution involves multiplying the fraction by the number of cupcakes and rounding up to the nearest whole pack:

80 × 2/25 = 160/25 = 6.4 packs

Highlight: When dealing with real-world problems, remember to round up to the nearest whole unit when partial units aren't practical.

Significant Figures

This page introduces the concept of significant figures in rounding numbers.

Definition: The first significant figure is the first non-zero digit from the left. Subsequent digits, including zeros, are counted as significant figures.

Example: In 0.002309, the significant figures are: 1st: 2 2nd: 3 3rd: 0 4th: 9

Highlight: Understanding significant figures is crucial for maintaining precision in scientific and engineering calculations.

Rounding to Significant Figures

This section demonstrates how to round numbers to a specified number of significant figures.

Example: Rounding 506.07 to two significant figures:

1. Identify the first two significant digits (50)
2. Look at the next digit (6) as the decider
3. Since 6 ≥ 5, round up Result: 510

Highlight: When rounding to significant figures, you may need to add zeros to maintain the correct magnitude of the number.