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Finding the Fourth Proportional to 612.84, 919.26 and 431.05

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Solution

The fourth proportional to 612.84, 919.26 and 431.05 is: 646.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.84 : 919.26 = 431.05 : x
  2. Step 2: Convert to fraction form
    612.84/919.26 = 431.05/x
  3. Step 3: Cross multiply
    612.84x = 919.26 × 431.05
  4. Step 4: Simplify right side
    612.84x = 396,244.72
  5. Step 5: Solve for x
    x = 396,244.72/612.84
  6. Step 6: Final answer
    x = 646.57

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Similar ratio
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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.