Home / 394.88-545.15-255.20

Finding the Fourth Proportional to 394.88, 545.15 and 255.20

Calculator

Solution

The fourth proportional to 394.88, 545.15 and 255.20 is: 352.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    394.88 : 545.15 = 255.20 : x
  2. Step 2: Convert to fraction form
    394.88/545.15 = 255.20/x
  3. Step 3: Cross multiply
    394.88x = 545.15 × 255.20
  4. Step 4: Simplify right side
    394.88x = 139,120.19
  5. Step 5: Solve for x
    x = 139,120.19/394.88
  6. Step 6: Final answer
    x = 352.31

Related Problems

Find fourth proportional to 197.44, 272.58 and 127.60
Half scale
Find fourth proportional to 789.75, 1,090.31 and 510.39
Double scale
Find fourth proportional to 395.88, 546.53 and 256.20
Similar ratio
Find fourth proportional to 592.31, 817.73 and 382.79
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.