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Finding the Fourth Proportional to 670.80, 1,005.90 and 305.70

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Solution

The fourth proportional to 670.80, 1,005.90 and 305.70 is: 458.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.80 : 1,005.90 = 305.70 : x
  2. Step 2: Convert to fraction form
    670.80/1,005.90 = 305.70/x
  3. Step 3: Cross multiply
    670.80x = 1,005.90 × 305.70
  4. Step 4: Simplify right side
    670.80x = 307,503.63
  5. Step 5: Solve for x
    x = 307,503.63/670.80
  6. Step 6: Final answer
    x = 458.41

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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.