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Finding the Fourth Proportional to 646.79, 970.38 and 256.95

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Solution

The fourth proportional to 646.79, 970.38 and 256.95 is: 385.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.79 : 970.38 = 256.95 : x
  2. Step 2: Convert to fraction form
    646.79/970.38 = 256.95/x
  3. Step 3: Cross multiply
    646.79x = 970.38 × 256.95
  4. Step 4: Simplify right side
    646.79x = 249,339.14
  5. Step 5: Solve for x
    x = 249,339.14/646.79
  6. Step 6: Final answer
    x = 385.51

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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.