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Finding the Fourth Proportional to 817.31, 1,128.46 and 630.51

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Solution

The fourth proportional to 817.31, 1,128.46 and 630.51 is: 870.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    817.31 : 1,128.46 = 630.51 : x
  2. Step 2: Convert to fraction form
    817.31/1,128.46 = 630.51/x
  3. Step 3: Cross multiply
    817.31x = 1,128.46 × 630.51
  4. Step 4: Simplify right side
    817.31x = 711,505.31
  5. Step 5: Solve for x
    x = 711,505.31/817.31
  6. Step 6: Final answer
    x = 870.55

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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.