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Finding the Fourth Proportional to 989.47, 1,484.43 and 340.21

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Solution

The fourth proportional to 989.47, 1,484.43 and 340.21 is: 510.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    989.47 : 1,484.43 = 340.21 : x
  2. Step 2: Convert to fraction form
    989.47/1,484.43 = 340.21/x
  3. Step 3: Cross multiply
    989.47x = 1,484.43 × 340.21
  4. Step 4: Simplify right side
    989.47x = 505,017.93
  5. Step 5: Solve for x
    x = 505,017.93/989.47
  6. Step 6: Final answer
    x = 510.39

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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.