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Finding the Fourth Proportional to 840.07, 1,260.12 and 255.09

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Solution

The fourth proportional to 840.07, 1,260.12 and 255.09 is: 382.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.07 : 1,260.12 = 255.09 : x
  2. Step 2: Convert to fraction form
    840.07/1,260.12 = 255.09/x
  3. Step 3: Cross multiply
    840.07x = 1,260.12 × 255.09
  4. Step 4: Simplify right side
    840.07x = 321,444.01
  5. Step 5: Solve for x
    x = 321,444.01/840.07
  6. Step 6: Final answer
    x = 382.64

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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.