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Finding the Fourth Proportional to 890.83, 1,226.80 and 641.76

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Solution

The fourth proportional to 890.83, 1,226.80 and 641.76 is: 883.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.83 : 1,226.80 = 641.76 : x
  2. Step 2: Convert to fraction form
    890.83/1,226.80 = 641.76/x
  3. Step 3: Cross multiply
    890.83x = 1,226.80 × 641.76
  4. Step 4: Simplify right side
    890.83x = 787,303.76
  5. Step 5: Solve for x
    x = 787,303.76/890.83
  6. Step 6: Final answer
    x = 883.79

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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.