Home / 571.71-857.55-138.86

Finding the Fourth Proportional to 571.71, 857.55 and 138.86

Calculator

Solution

The fourth proportional to 571.71, 857.55 and 138.86 is: 208.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    571.71 : 857.55 = 138.86 : x
  2. Step 2: Convert to fraction form
    571.71/857.55 = 138.86/x
  3. Step 3: Cross multiply
    571.71x = 857.55 × 138.86
  4. Step 4: Simplify right side
    571.71x = 119,079.39
  5. Step 5: Solve for x
    x = 119,079.39/571.71
  6. Step 6: Final answer
    x = 208.29

Related Problems

Find fourth proportional to 285.86, 428.78 and 69.43
Half scale
Find fourth proportional to 1,143.42, 1,715.10 and 277.72
Double scale
Find fourth proportional to 572.71, 859.05 and 139.86
Similar ratio
Find fourth proportional to 857.57, 1,286.33 and 208.29
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.