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Finding the Fourth Proportional to 666.12, 918.10 and 646.50

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Solution

The fourth proportional to 666.12, 918.10 and 646.50 is: 891.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.12 : 918.10 = 646.50 : x
  2. Step 2: Convert to fraction form
    666.12/918.10 = 646.50/x
  3. Step 3: Cross multiply
    666.12x = 918.10 × 646.50
  4. Step 4: Simplify right side
    666.12x = 593,551.65
  5. Step 5: Solve for x
    x = 593,551.65/666.12
  6. Step 6: Final answer
    x = 891.06

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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.