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Finding the Fourth Proportional to 491.12, 677.76 and 278.45

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Solution

The fourth proportional to 491.12, 677.76 and 278.45 is: 384.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.12 : 677.76 = 278.45 : x
  2. Step 2: Convert to fraction form
    491.12/677.76 = 278.45/x
  3. Step 3: Cross multiply
    491.12x = 677.76 × 278.45
  4. Step 4: Simplify right side
    491.12x = 188,718.88
  5. Step 5: Solve for x
    x = 188,718.88/491.12
  6. Step 6: Final answer
    x = 384.27

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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.