Home / 587.40-809.94-390.54

Finding the Fourth Proportional to 587.40, 809.94 and 390.54

Calculator

Solution

The fourth proportional to 587.40, 809.94 and 390.54 is: 538.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    587.40 : 809.94 = 390.54 : x
  2. Step 2: Convert to fraction form
    587.40/809.94 = 390.54/x
  3. Step 3: Cross multiply
    587.40x = 809.94 × 390.54
  4. Step 4: Simplify right side
    587.40x = 316,313.97
  5. Step 5: Solve for x
    x = 316,313.97/587.40
  6. Step 6: Final answer
    x = 538.50

Related Problems

Find fourth proportional to 293.70, 404.97 and 195.27
Half scale
Find fourth proportional to 1,174.80, 1,619.88 and 781.08
Double scale
Find fourth proportional to 588.40, 811.32 and 391.54
Similar ratio
Find fourth proportional to 881.10, 1,214.91 and 585.81
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.