Home / 128.76-193.21-67.90

Finding the Fourth Proportional to 128.76, 193.21 and 67.90

Calculator

Solution

The fourth proportional to 128.76, 193.21 and 67.90 is: 101.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.76 : 193.21 = 67.90 : x
  2. Step 2: Convert to fraction form
    128.76/193.21 = 67.90/x
  3. Step 3: Cross multiply
    128.76x = 193.21 × 67.90
  4. Step 4: Simplify right side
    128.76x = 13,118.31
  5. Step 5: Solve for x
    x = 13,118.31/128.76
  6. Step 6: Final answer
    x = 101.88

Related Problems

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.