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Finding the Fourth Proportional to 497.78, 686.58 and 320.76

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Solution

The fourth proportional to 497.78, 686.58 and 320.76 is: 442.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    497.78 : 686.58 = 320.76 : x
  2. Step 2: Convert to fraction form
    497.78/686.58 = 320.76/x
  3. Step 3: Cross multiply
    497.78x = 686.58 × 320.76
  4. Step 4: Simplify right side
    497.78x = 220,227.40
  5. Step 5: Solve for x
    x = 220,227.40/497.78
  6. Step 6: Final answer
    x = 442.42

Related Problems

Find fourth proportional to 248.89, 343.29 and 160.38
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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.