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Finding the Fourth Proportional to 612.56, 918.57 and 287.75

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Solution

The fourth proportional to 612.56, 918.57 and 287.75 is: 431.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.56 : 918.57 = 287.75 : x
  2. Step 2: Convert to fraction form
    612.56/918.57 = 287.75/x
  3. Step 3: Cross multiply
    612.56x = 918.57 × 287.75
  4. Step 4: Simplify right side
    612.56x = 264,318.52
  5. Step 5: Solve for x
    x = 264,318.52/612.56
  6. Step 6: Final answer
    x = 431.50

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Similar ratio
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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.