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Finding the Fourth Proportional to 856.40, 1,181.94 and 621.12

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Solution

The fourth proportional to 856.40, 1,181.94 and 621.12 is: 857.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.40 : 1,181.94 = 621.12 : x
  2. Step 2: Convert to fraction form
    856.40/1,181.94 = 621.12/x
  3. Step 3: Cross multiply
    856.40x = 1,181.94 × 621.12
  4. Step 4: Simplify right side
    856.40x = 734,126.57
  5. Step 5: Solve for x
    x = 734,126.57/856.40
  6. Step 6: Final answer
    x = 857.22

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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.