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Finding the Fourth Proportional to 813.51, 1,220.26 and 521.16

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Solution

The fourth proportional to 813.51, 1,220.26 and 521.16 is: 781.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.51 : 1,220.26 = 521.16 : x
  2. Step 2: Convert to fraction form
    813.51/1,220.26 = 521.16/x
  3. Step 3: Cross multiply
    813.51x = 1,220.26 × 521.16
  4. Step 4: Simplify right side
    813.51x = 635,950.70
  5. Step 5: Solve for x
    x = 635,950.70/813.51
  6. Step 6: Final answer
    x = 781.74

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Double scale
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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.