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Finding the Fourth Proportional to 852.59, 1,281.35 and 420.05

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Solution

The fourth proportional to 852.59, 1,281.35 and 420.05 is: 631.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    852.59 : 1,281.35 = 420.05 : x
  2. Step 2: Convert to fraction form
    852.59/1,281.35 = 420.05/x
  3. Step 3: Cross multiply
    852.59x = 1,281.35 × 420.05
  4. Step 4: Simplify right side
    852.59x = 538,235.32
  5. Step 5: Solve for x
    x = 538,235.32/852.59
  6. Step 6: Final answer
    x = 631.29

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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.