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Finding the Fourth Proportional to 856.30, 1,284.15 and 445.30

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Solution

The fourth proportional to 856.30, 1,284.15 and 445.30 is: 667.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.30 : 1,284.15 = 445.30 : x
  2. Step 2: Convert to fraction form
    856.30/1,284.15 = 445.30/x
  3. Step 3: Cross multiply
    856.30x = 1,284.15 × 445.30
  4. Step 4: Simplify right side
    856.30x = 571,832.00
  5. Step 5: Solve for x
    x = 571,832.00/856.30
  6. Step 6: Final answer
    x = 667.79

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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.