Home / 442.80-660.42-394.20

Finding the Fourth Proportional to 442.80, 660.42 and 394.20

Calculator

Solution

The fourth proportional to 442.80, 660.42 and 394.20 is: 587.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    442.80 : 660.42 = 394.20 : x
  2. Step 2: Convert to fraction form
    442.80/660.42 = 394.20/x
  3. Step 3: Cross multiply
    442.80x = 660.42 × 394.20
  4. Step 4: Simplify right side
    442.80x = 260,337.56
  5. Step 5: Solve for x
    x = 260,337.56/442.80
  6. Step 6: Final answer
    x = 587.93

Related Problems

Find fourth proportional to 221.40, 330.21 and 197.10
Half scale
Find fourth proportional to 885.60, 1,320.84 and 788.40
Double scale
Find fourth proportional to 443.80, 661.91 and 395.20
Similar ratio
Find fourth proportional to 664.20, 990.63 and 591.30
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.