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Finding the Fourth Proportional to 715.61, 988.64 and 611.78

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Solution

The fourth proportional to 715.61, 988.64 and 611.78 is: 845.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    715.61 : 988.64 = 611.78 : x
  2. Step 2: Convert to fraction form
    715.61/988.64 = 611.78/x
  3. Step 3: Cross multiply
    715.61x = 988.64 × 611.78
  4. Step 4: Simplify right side
    715.61x = 604,822.18
  5. Step 5: Solve for x
    x = 604,822.18/715.61
  6. Step 6: Final answer
    x = 845.19

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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.