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Finding the Fourth Proportional to 691.41, 1,031.79 and 618.51

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Solution

The fourth proportional to 691.41, 1,031.79 and 618.51 is: 923.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.41 : 1,031.79 = 618.51 : x
  2. Step 2: Convert to fraction form
    691.41/1,031.79 = 618.51/x
  3. Step 3: Cross multiply
    691.41x = 1,031.79 × 618.51
  4. Step 4: Simplify right side
    691.41x = 638,172.43
  5. Step 5: Solve for x
    x = 638,172.43/691.41
  6. Step 6: Final answer
    x = 923.00

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.