Home / 138.88-207.32-128.88

Finding the Fourth Proportional to 138.88, 207.32 and 128.88

Calculator

Solution

The fourth proportional to 138.88, 207.32 and 128.88 is: 192.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.88 : 207.32 = 128.88 : x
  2. Step 2: Convert to fraction form
    138.88/207.32 = 128.88/x
  3. Step 3: Cross multiply
    138.88x = 207.32 × 128.88
  4. Step 4: Simplify right side
    138.88x = 26,719.40
  5. Step 5: Solve for x
    x = 26,719.40/138.88
  6. Step 6: Final answer
    x = 192.39

Related Problems

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.