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Finding the Fourth Proportional to 687.39, 942.99 and 666.58

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Solution

The fourth proportional to 687.39, 942.99 and 666.58 is: 914.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.39 : 942.99 = 666.58 : x
  2. Step 2: Convert to fraction form
    687.39/942.99 = 666.58/x
  3. Step 3: Cross multiply
    687.39x = 942.99 × 666.58
  4. Step 4: Simplify right side
    687.39x = 628,578.93
  5. Step 5: Solve for x
    x = 628,578.93/687.39
  6. Step 6: Final answer
    x = 914.45

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.