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Finding the Fourth Proportional to 670.90, 1,006.16 and 259.80

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Solution

The fourth proportional to 670.90, 1,006.16 and 259.80 is: 389.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.90 : 1,006.16 = 259.80 : x
  2. Step 2: Convert to fraction form
    670.90/1,006.16 = 259.80/x
  3. Step 3: Cross multiply
    670.90x = 1,006.16 × 259.80
  4. Step 4: Simplify right side
    670.90x = 261,399.07
  5. Step 5: Solve for x
    x = 261,399.07/670.90
  6. Step 6: Final answer
    x = 389.63

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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.