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Finding the Fourth Proportional to 302.40, 419.55 and 278.10

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Solution

The fourth proportional to 302.40, 419.55 and 278.10 is: 385.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    302.40 : 419.55 = 278.10 : x
  2. Step 2: Convert to fraction form
    302.40/419.55 = 278.10/x
  3. Step 3: Cross multiply
    302.40x = 419.55 × 278.10
  4. Step 4: Simplify right side
    302.40x = 116,675.81
  5. Step 5: Solve for x
    x = 116,675.81/302.40
  6. Step 6: Final answer
    x = 385.83

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.