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Finding the Fourth Proportional to 780.99, 1,172.66 and 490.34

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Solution

The fourth proportional to 780.99, 1,172.66 and 490.34 is: 736.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.99 : 1,172.66 = 490.34 : x
  2. Step 2: Convert to fraction form
    780.99/1,172.66 = 490.34/x
  3. Step 3: Cross multiply
    780.99x = 1,172.66 × 490.34
  4. Step 4: Simplify right side
    780.99x = 574,993.79
  5. Step 5: Solve for x
    x = 574,993.79/780.99
  6. Step 6: Final answer
    x = 736.24

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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.