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Finding the Fourth Proportional to 646.99, 970.79 and 511.21

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Solution

The fourth proportional to 646.99, 970.79 and 511.21 is: 767.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.99 : 970.79 = 511.21 : x
  2. Step 2: Convert to fraction form
    646.99/970.79 = 511.21/x
  3. Step 3: Cross multiply
    646.99x = 970.79 × 511.21
  4. Step 4: Simplify right side
    646.99x = 496,276.21
  5. Step 5: Solve for x
    x = 496,276.21/646.99
  6. Step 6: Final answer
    x = 767.06

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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.