Home / 320.55-478.64-254.81

Finding the Fourth Proportional to 320.55, 478.64 and 254.81

Calculator

Solution

The fourth proportional to 320.55, 478.64 and 254.81 is: 380.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.55 : 478.64 = 254.81 : x
  2. Step 2: Convert to fraction form
    320.55/478.64 = 254.81/x
  3. Step 3: Cross multiply
    320.55x = 478.64 × 254.81
  4. Step 4: Simplify right side
    320.55x = 121,962.26
  5. Step 5: Solve for x
    x = 121,962.26/320.55
  6. Step 6: Final answer
    x = 380.48

Related Problems

Find fourth proportional to 160.28, 239.32 and 127.41
Half scale
Find fourth proportional to 641.10, 957.28 and 509.62
Double scale
Find fourth proportional to 321.55, 480.13 and 255.81
Similar ratio
Find fourth proportional to 480.83, 717.96 and 382.22
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.