Home / 138.79-207.90-66.58

Finding the Fourth Proportional to 138.79, 207.90 and 66.58

Calculator

Solution

The fourth proportional to 138.79, 207.90 and 66.58 is: 99.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.79 : 207.90 = 66.58 : x
  2. Step 2: Convert to fraction form
    138.79/207.90 = 66.58/x
  3. Step 3: Cross multiply
    138.79x = 207.90 × 66.58
  4. Step 4: Simplify right side
    138.79x = 13,841.98
  5. Step 5: Solve for x
    x = 13,841.98/138.79
  6. Step 6: Final answer
    x = 99.73

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.