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Finding the Fourth Proportional to 403.21, 555.72 and 278.65

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Solution

The fourth proportional to 403.21, 555.72 and 278.65 is: 384.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.21 : 555.72 = 278.65 : x
  2. Step 2: Convert to fraction form
    403.21/555.72 = 278.65/x
  3. Step 3: Cross multiply
    403.21x = 555.72 × 278.65
  4. Step 4: Simplify right side
    403.21x = 154,851.38
  5. Step 5: Solve for x
    x = 154,851.38/403.21
  6. Step 6: Final answer
    x = 384.05

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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.