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Finding the Fourth Proportional to 678.93, 1,018.40 and 435.62

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Solution

The fourth proportional to 678.93, 1,018.40 and 435.62 is: 653.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.93 : 1,018.40 = 435.62 : x
  2. Step 2: Convert to fraction form
    678.93/1,018.40 = 435.62/x
  3. Step 3: Cross multiply
    678.93x = 1,018.40 × 435.62
  4. Step 4: Simplify right side
    678.93x = 443,628.14
  5. Step 5: Solve for x
    x = 443,628.14/678.93
  6. Step 6: Final answer
    x = 653.42

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.