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Finding the Fourth Proportional to 665.80, 918.81 and 371.10

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Solution

The fourth proportional to 665.80, 918.81 and 371.10 is: 512.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.80 : 918.81 = 371.10 : x
  2. Step 2: Convert to fraction form
    665.80/918.81 = 371.10/x
  3. Step 3: Cross multiply
    665.80x = 918.81 × 371.10
  4. Step 4: Simplify right side
    665.80x = 340,973.84
  5. Step 5: Solve for x
    x = 340,973.84/665.80
  6. Step 6: Final answer
    x = 512.13

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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.