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Finding the Fourth Proportional to 987.10, 1,478.30 and 830.16

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Solution

The fourth proportional to 987.10, 1,478.30 and 830.16 is: 1,243.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    987.10 : 1,478.30 = 830.16 : x
  2. Step 2: Convert to fraction form
    987.10/1,478.30 = 830.16/x
  3. Step 3: Cross multiply
    987.10x = 1,478.30 × 830.16
  4. Step 4: Simplify right side
    987.10x = 1,227,225.53
  5. Step 5: Solve for x
    x = 1,227,225.53/987.10
  6. Step 6: Final answer
    x = 1,243.26

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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.