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Finding the Fourth Proportional to 855.84, 1,284.10 and 278.72

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Solution

The fourth proportional to 855.84, 1,284.10 and 278.72 is: 418.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    855.84 : 1,284.10 = 278.72 : x
  2. Step 2: Convert to fraction form
    855.84/1,284.10 = 278.72/x
  3. Step 3: Cross multiply
    855.84x = 1,284.10 × 278.72
  4. Step 4: Simplify right side
    855.84x = 357,904.35
  5. Step 5: Solve for x
    x = 357,904.35/855.84
  6. Step 6: Final answer
    x = 418.19

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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.