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Finding the Fourth Proportional to 618.70, 865.10 and 618.70

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Solution

The fourth proportional to 618.70, 865.10 and 618.70 is: 865.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.70 : 865.10 = 618.70 : x
  2. Step 2: Convert to fraction form
    618.70/865.10 = 618.70/x
  3. Step 3: Cross multiply
    618.70x = 865.10 × 618.70
  4. Step 4: Simplify right side
    618.70x = 535,237.37
  5. Step 5: Solve for x
    x = 535,237.37/618.70
  6. Step 6: Final answer
    x = 865.10

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.