Home / 147.20-203.14-81.70

Finding the Fourth Proportional to 147.20, 203.14 and 81.70

Calculator

Solution

The fourth proportional to 147.20, 203.14 and 81.70 is: 112.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    147.20 : 203.14 = 81.70 : x
  2. Step 2: Convert to fraction form
    147.20/203.14 = 81.70/x
  3. Step 3: Cross multiply
    147.20x = 203.14 × 81.70
  4. Step 4: Simplify right side
    147.20x = 16,595.83
  5. Step 5: Solve for x
    x = 16,595.83/147.20
  6. Step 6: Final answer
    x = 112.75

Related Problems

Find fourth proportional to 73.60, 101.57 and 40.85
Half scale
Find fourth proportional to 294.39, 406.28 and 163.40
Double scale
Find fourth proportional to 148.20, 204.52 and 82.70
Similar ratio
Find fourth proportional to 220.79, 304.71 and 122.55
1.5x scale

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.