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Finding the Fourth Proportional to 1,319.50, 1,980.18 and 550

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Solution

The fourth proportional to 1,319.50, 1,980.18 and 550 is: 825.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.50 : 1,980.18 = 550 : x
  2. Step 2: Convert to fraction form
    1,319.50/1,980.18 = 550/x
  3. Step 3: Cross multiply
    1,319.50x = 1,980.18 × 550
  4. Step 4: Simplify right side
    1,319.50x = 1,089,099
  5. Step 5: Solve for x
    x = 1,089,099/1,319.50
  6. Step 6: Final answer
    x = 825.39

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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.