Home / 132.45-198.69-78.31

Finding the Fourth Proportional to 132.45, 198.69 and 78.31

Calculator

Solution

The fourth proportional to 132.45, 198.69 and 78.31 is: 117.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    132.45 : 198.69 = 78.31 : x
  2. Step 2: Convert to fraction form
    132.45/198.69 = 78.31/x
  3. Step 3: Cross multiply
    132.45x = 198.69 × 78.31
  4. Step 4: Simplify right side
    132.45x = 15,559.41
  5. Step 5: Solve for x
    x = 15,559.41/132.45
  6. Step 6: Final answer
    x = 117.47

Related Problems

Find fourth proportional to 66.23, 99.35 and 39.16
Half scale
Find fourth proportional to 264.90, 397.38 and 156.62
Double scale
Find fourth proportional to 133.45, 200.19 and 79.31
Similar ratio
Find fourth proportional to 198.68, 298.04 and 117.47
1.5x scale

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.