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Finding the Fourth Proportional to 678.64, 937.24 and 668.40

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Solution

The fourth proportional to 678.64, 937.24 and 668.40 is: 923.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.64 : 937.24 = 668.40 : x
  2. Step 2: Convert to fraction form
    678.64/937.24 = 668.40/x
  3. Step 3: Cross multiply
    678.64x = 937.24 × 668.40
  4. Step 4: Simplify right side
    678.64x = 626,451.22
  5. Step 5: Solve for x
    x = 626,451.22/678.64
  6. Step 6: Final answer
    x = 923.10

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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.