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Finding the Fourth Proportional to 810.93, 1,216.50 and 421.12

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Solution

The fourth proportional to 810.93, 1,216.50 and 421.12 is: 631.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.93 : 1,216.50 = 421.12 : x
  2. Step 2: Convert to fraction form
    810.93/1,216.50 = 421.12/x
  3. Step 3: Cross multiply
    810.93x = 1,216.50 × 421.12
  4. Step 4: Simplify right side
    810.93x = 512,284.29
  5. Step 5: Solve for x
    x = 512,284.29/810.93
  6. Step 6: Final answer
    x = 631.72

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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.