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Finding the Fourth Proportional to 403.19, 555.21 and 394.10

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Solution

The fourth proportional to 403.19, 555.21 and 394.10 is: 542.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.19 : 555.21 = 394.10 : x
  2. Step 2: Convert to fraction form
    403.19/555.21 = 394.10/x
  3. Step 3: Cross multiply
    403.19x = 555.21 × 394.10
  4. Step 4: Simplify right side
    403.19x = 218,808.26
  5. Step 5: Solve for x
    x = 218,808.26/403.19
  6. Step 6: Final answer
    x = 542.69

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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.