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Finding the Fourth Proportional to 810.45, 1,118.82 and 478.98

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Solution

The fourth proportional to 810.45, 1,118.82 and 478.98 is: 661.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.45 : 1,118.82 = 478.98 : x
  2. Step 2: Convert to fraction form
    810.45/1,118.82 = 478.98/x
  3. Step 3: Cross multiply
    810.45x = 1,118.82 × 478.98
  4. Step 4: Simplify right side
    810.45x = 535,892.40
  5. Step 5: Solve for x
    x = 535,892.40/810.45
  6. Step 6: Final answer
    x = 661.23

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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.