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Finding the Fourth Proportional to 647.40, 970.03 and 338.79

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Solution

The fourth proportional to 647.40, 970.03 and 338.79 is: 507.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.40 : 970.03 = 338.79 : x
  2. Step 2: Convert to fraction form
    647.40/970.03 = 338.79/x
  3. Step 3: Cross multiply
    647.40x = 970.03 × 338.79
  4. Step 4: Simplify right side
    647.40x = 328,636.46
  5. Step 5: Solve for x
    x = 328,636.46/647.40
  6. Step 6: Final answer
    x = 507.63

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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.