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Finding the Fourth Proportional to 811.88, 1,120.69 and 497.08

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Solution

The fourth proportional to 811.88, 1,120.69 and 497.08 is: 686.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.88 : 1,120.69 = 497.08 : x
  2. Step 2: Convert to fraction form
    811.88/1,120.69 = 497.08/x
  3. Step 3: Cross multiply
    811.88x = 1,120.69 × 497.08
  4. Step 4: Simplify right side
    811.88x = 557,066.91
  5. Step 5: Solve for x
    x = 557,066.91/811.88
  6. Step 6: Final answer
    x = 686.14

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Double scale
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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.