Home / 128.15-176.85-72.89

Finding the Fourth Proportional to 128.15, 176.85 and 72.89

Calculator

Solution

The fourth proportional to 128.15, 176.85 and 72.89 is: 100.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.15 : 176.85 = 72.89 : x
  2. Step 2: Convert to fraction form
    128.15/176.85 = 72.89/x
  3. Step 3: Cross multiply
    128.15x = 176.85 × 72.89
  4. Step 4: Simplify right side
    128.15x = 12,890.60
  5. Step 5: Solve for x
    x = 12,890.60/128.15
  6. Step 6: Final answer
    x = 100.59

Related Problems

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.