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Finding the Fourth Proportional to 811.85, 1,120.08 and 457.71

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Solution

The fourth proportional to 811.85, 1,120.08 and 457.71 is: 631.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.85 : 1,120.08 = 457.71 : x
  2. Step 2: Convert to fraction form
    811.85/1,120.08 = 457.71/x
  3. Step 3: Cross multiply
    811.85x = 1,120.08 × 457.71
  4. Step 4: Simplify right side
    811.85x = 512,674.63
  5. Step 5: Solve for x
    x = 512,674.63/811.85
  6. Step 6: Final answer
    x = 631.49

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Double scale
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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.