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Finding the Fourth Proportional to 665.40, 918.06 and 403.50

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Solution

The fourth proportional to 665.40, 918.06 and 403.50 is: 556.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 918.06 = 403.50 : x
  2. Step 2: Convert to fraction form
    665.40/918.06 = 403.50/x
  3. Step 3: Cross multiply
    665.40x = 918.06 × 403.50
  4. Step 4: Simplify right side
    665.40x = 370,437.21
  5. Step 5: Solve for x
    x = 370,437.21/665.40
  6. Step 6: Final answer
    x = 556.71

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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.