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Finding the Fourth Proportional to 803.53, 1,205.30 and 419.53

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Solution

The fourth proportional to 803.53, 1,205.30 and 419.53 is: 629.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    803.53 : 1,205.30 = 419.53 : x
  2. Step 2: Convert to fraction form
    803.53/1,205.30 = 419.53/x
  3. Step 3: Cross multiply
    803.53x = 1,205.30 × 419.53
  4. Step 4: Simplify right side
    803.53x = 505,657.41
  5. Step 5: Solve for x
    x = 505,657.41/803.53
  6. Step 6: Final answer
    x = 629.30

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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.