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Finding the Fourth Proportional to 646.95, 970.80 and 387.59

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Solution

The fourth proportional to 646.95, 970.80 and 387.59 is: 581.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.95 : 970.80 = 387.59 : x
  2. Step 2: Convert to fraction form
    646.95/970.80 = 387.59/x
  3. Step 3: Cross multiply
    646.95x = 970.80 × 387.59
  4. Step 4: Simplify right side
    646.95x = 376,267.52
  5. Step 5: Solve for x
    x = 376,267.52/646.95
  6. Step 6: Final answer
    x = 581.60

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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.