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Finding the Fourth Proportional to 784.30, 1,177.05 and 419.39

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Solution

The fourth proportional to 784.30, 1,177.05 and 419.39 is: 629.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.30 : 1,177.05 = 419.39 : x
  2. Step 2: Convert to fraction form
    784.30/1,177.05 = 419.39/x
  3. Step 3: Cross multiply
    784.30x = 1,177.05 × 419.39
  4. Step 4: Simplify right side
    784.30x = 493,643.00
  5. Step 5: Solve for x
    x = 493,643.00/784.30
  6. Step 6: Final answer
    x = 629.41

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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.