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Finding the Fourth Proportional to 670.11, 1,005.40 and 304.78

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Solution

The fourth proportional to 670.11, 1,005.40 and 304.78 is: 457.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.11 : 1,005.40 = 304.78 : x
  2. Step 2: Convert to fraction form
    670.11/1,005.40 = 304.78/x
  3. Step 3: Cross multiply
    670.11x = 1,005.40 × 304.78
  4. Step 4: Simplify right side
    670.11x = 306,425.81
  5. Step 5: Solve for x
    x = 306,425.81/670.11
  6. Step 6: Final answer
    x = 457.28

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.