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Finding the Fourth Proportional to 689.04, 1,031.81 and 410.81

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Solution

The fourth proportional to 689.04, 1,031.81 and 410.81 is: 615.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.04 : 1,031.81 = 410.81 : x
  2. Step 2: Convert to fraction form
    689.04/1,031.81 = 410.81/x
  3. Step 3: Cross multiply
    689.04x = 1,031.81 × 410.81
  4. Step 4: Simplify right side
    689.04x = 423,870.65
  5. Step 5: Solve for x
    x = 423,870.65/689.04
  6. Step 6: Final answer
    x = 615.16

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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.