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Finding the Fourth Proportional to 418.76, 578.08 and 279.11

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Solution

The fourth proportional to 418.76, 578.08 and 279.11 is: 385.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.76 : 578.08 = 279.11 : x
  2. Step 2: Convert to fraction form
    418.76/578.08 = 279.11/x
  3. Step 3: Cross multiply
    418.76x = 578.08 × 279.11
  4. Step 4: Simplify right side
    418.76x = 161,347.51
  5. Step 5: Solve for x
    x = 161,347.51/418.76
  6. Step 6: Final answer
    x = 385.30

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Find fourth proportional to 209.38, 289.04 and 139.55
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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.