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Finding the Fourth Proportional to 660.74, 990.35 and 513.39

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Solution

The fourth proportional to 660.74, 990.35 and 513.39 is: 769.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.74 : 990.35 = 513.39 : x
  2. Step 2: Convert to fraction form
    660.74/990.35 = 513.39/x
  3. Step 3: Cross multiply
    660.74x = 990.35 × 513.39
  4. Step 4: Simplify right side
    660.74x = 508,437.07
  5. Step 5: Solve for x
    x = 508,437.07/660.74
  6. Step 6: Final answer
    x = 769.50

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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.