Home / 488.72-674.38-278.90

Finding the Fourth Proportional to 488.72, 674.38 and 278.90

Calculator

Solution

The fourth proportional to 488.72, 674.38 and 278.90 is: 384.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    488.72 : 674.38 = 278.90 : x
  2. Step 2: Convert to fraction form
    488.72/674.38 = 278.90/x
  3. Step 3: Cross multiply
    488.72x = 674.38 × 278.90
  4. Step 4: Simplify right side
    488.72x = 188,081.56
  5. Step 5: Solve for x
    x = 188,081.56/488.72
  6. Step 6: Final answer
    x = 384.85

Related Problems

Find fourth proportional to 244.36, 337.19 and 139.45
Half scale
Find fourth proportional to 977.44, 1,348.76 and 557.79
Double scale
Find fourth proportional to 489.72, 675.76 and 279.90
Similar ratio
Find fourth proportional to 733.08, 1,011.57 and 418.34
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.