Home / 585.30-808.20-389.70

Finding the Fourth Proportional to 585.30, 808.20 and 389.70

Calculator

Solution

The fourth proportional to 585.30, 808.20 and 389.70 is: 538.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    585.30 : 808.20 = 389.70 : x
  2. Step 2: Convert to fraction form
    585.30/808.20 = 389.70/x
  3. Step 3: Cross multiply
    585.30x = 808.20 × 389.70
  4. Step 4: Simplify right side
    585.30x = 314,955.54
  5. Step 5: Solve for x
    x = 314,955.54/585.30
  6. Step 6: Final answer
    x = 538.11

Related Problems

Find fourth proportional to 292.65, 404.10 and 194.85
Half scale
Find fourth proportional to 1,170.60, 1,616.40 and 779.40
Double scale
Find fourth proportional to 586.30, 809.58 and 390.70
Similar ratio
Find fourth proportional to 877.95, 1,212.30 and 584.55
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.