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Finding the Fourth Proportional to 810.42, 1,214.45 and 439.91

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Solution

The fourth proportional to 810.42, 1,214.45 and 439.91 is: 659.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.42 : 1,214.45 = 439.91 : x
  2. Step 2: Convert to fraction form
    810.42/1,214.45 = 439.91/x
  3. Step 3: Cross multiply
    810.42x = 1,214.45 × 439.91
  4. Step 4: Simplify right side
    810.42x = 534,240.43
  5. Step 5: Solve for x
    x = 534,240.43/810.42
  6. Step 6: Final answer
    x = 659.21

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1.5x scale

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.