Home / 257.28-386-74.68

Finding the Fourth Proportional to 257.28, 386 and 74.68

Calculator

Solution

The fourth proportional to 257.28, 386 and 74.68 is: 112.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.28 : 386 = 74.68 : x
  2. Step 2: Convert to fraction form
    257.28/386 = 74.68/x
  3. Step 3: Cross multiply
    257.28x = 386 × 74.68
  4. Step 4: Simplify right side
    257.28x = 28,826.48
  5. Step 5: Solve for x
    x = 28,826.48/257.28
  6. Step 6: Final answer
    x = 112.04

Related Problems

Find fourth proportional to 128.64, 193 and 37.34
Half scale
Find fourth proportional to 514.56, 772 and 149.36
Double scale
Find fourth proportional to 258.28, 387.50 and 75.68
Similar ratio
Find fourth proportional to 385.92, 579 and 112.02
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.