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Finding the Fourth Proportional to 1,290.18, 1,935.09 and 520.50

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Solution

The fourth proportional to 1,290.18, 1,935.09 and 520.50 is: 780.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,290.18 : 1,935.09 = 520.50 : x
  2. Step 2: Convert to fraction form
    1,290.18/1,935.09 = 520.50/x
  3. Step 3: Cross multiply
    1,290.18x = 1,935.09 × 520.50
  4. Step 4: Simplify right side
    1,290.18x = 1,007,214.35
  5. Step 5: Solve for x
    x = 1,007,214.35/1,290.18
  6. Step 6: Final answer
    x = 780.68

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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.