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Finding the Fourth Proportional to 1,089.70, 1,634.55 and 657.70

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Solution

The fourth proportional to 1,089.70, 1,634.55 and 657.70 is: 986.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,089.70 : 1,634.55 = 657.70 : x
  2. Step 2: Convert to fraction form
    1,089.70/1,634.55 = 657.70/x
  3. Step 3: Cross multiply
    1,089.70x = 1,634.55 × 657.70
  4. Step 4: Simplify right side
    1,089.70x = 1,075,043.54
  5. Step 5: Solve for x
    x = 1,075,043.54/1,089.70
  6. Step 6: Final answer
    x = 986.55

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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.