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Finding the Fourth Proportional to 896.80, 1,345.20 and 459.40

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Solution

The fourth proportional to 896.80, 1,345.20 and 459.40 is: 689.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    896.80 : 1,345.20 = 459.40 : x
  2. Step 2: Convert to fraction form
    896.80/1,345.20 = 459.40/x
  3. Step 3: Cross multiply
    896.80x = 1,345.20 × 459.40
  4. Step 4: Simplify right side
    896.80x = 617,984.88
  5. Step 5: Solve for x
    x = 617,984.88/896.80
  6. Step 6: Final answer
    x = 689.10

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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.