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Finding the Fourth Proportional to 810.98, 1,214.64 and 485.66

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Solution

The fourth proportional to 810.98, 1,214.64 and 485.66 is: 727.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.98 : 1,214.64 = 485.66 : x
  2. Step 2: Convert to fraction form
    810.98/1,214.64 = 485.66/x
  3. Step 3: Cross multiply
    810.98x = 1,214.64 × 485.66
  4. Step 4: Simplify right side
    810.98x = 589,902.06
  5. Step 5: Solve for x
    x = 589,902.06/810.98
  6. Step 6: Final answer
    x = 727.39

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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.