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Finding the Fourth Proportional to 678.51, 934.36 and 491.69

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Solution

The fourth proportional to 678.51, 934.36 and 491.69 is: 677.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.51 : 934.36 = 491.69 : x
  2. Step 2: Convert to fraction form
    678.51/934.36 = 491.69/x
  3. Step 3: Cross multiply
    678.51x = 934.36 × 491.69
  4. Step 4: Simplify right side
    678.51x = 459,416.58
  5. Step 5: Solve for x
    x = 459,416.58/678.51
  6. Step 6: Final answer
    x = 677.10

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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.