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Finding the Fourth Proportional to 630.78, 869.80 and 497.77

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Solution

The fourth proportional to 630.78, 869.80 and 497.77 is: 686.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.78 : 869.80 = 497.77 : x
  2. Step 2: Convert to fraction form
    630.78/869.80 = 497.77/x
  3. Step 3: Cross multiply
    630.78x = 869.80 × 497.77
  4. Step 4: Simplify right side
    630.78x = 432,960.35
  5. Step 5: Solve for x
    x = 432,960.35/630.78
  6. Step 6: Final answer
    x = 686.39

Related Problems

Find fourth proportional to 315.39, 434.90 and 248.89
Half scale
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Double scale
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Similar ratio
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1.5x scale

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.