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Finding the Fourth Proportional to 909.50, 1,255.64 and 615.20

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Solution

The fourth proportional to 909.50, 1,255.64 and 615.20 is: 849.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    909.50 : 1,255.64 = 615.20 : x
  2. Step 2: Convert to fraction form
    909.50/1,255.64 = 615.20/x
  3. Step 3: Cross multiply
    909.50x = 1,255.64 × 615.20
  4. Step 4: Simplify right side
    909.50x = 772,460.37
  5. Step 5: Solve for x
    x = 772,460.37/909.50
  6. Step 6: Final answer
    x = 849.33

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.