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Finding the Fourth Proportional to 810.90, 1,118.97 and 479.30

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Solution

The fourth proportional to 810.90, 1,118.97 and 479.30 is: 661.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.90 : 1,118.97 = 479.30 : x
  2. Step 2: Convert to fraction form
    810.90/1,118.97 = 479.30/x
  3. Step 3: Cross multiply
    810.90x = 1,118.97 × 479.30
  4. Step 4: Simplify right side
    810.90x = 536,316.73
  5. Step 5: Solve for x
    x = 536,316.73/810.90
  6. Step 6: Final answer
    x = 661.38

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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.