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Finding the Fourth Proportional to 817.89, 1,128.38 and 538.28

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Solution

The fourth proportional to 817.89, 1,128.38 and 538.28 is: 742.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    817.89 : 1,128.38 = 538.28 : x
  2. Step 2: Convert to fraction form
    817.89/1,128.38 = 538.28/x
  3. Step 3: Cross multiply
    817.89x = 1,128.38 × 538.28
  4. Step 4: Simplify right side
    817.89x = 607,376.05
  5. Step 5: Solve for x
    x = 607,376.05/817.89
  6. Step 6: Final answer
    x = 742.61

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1.5x scale

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.