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Finding the Fourth Proportional to 621.37, 931.17 and 490.79

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Solution

The fourth proportional to 621.37, 931.17 and 490.79 is: 735.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.37 : 931.17 = 490.79 : x
  2. Step 2: Convert to fraction form
    621.37/931.17 = 490.79/x
  3. Step 3: Cross multiply
    621.37x = 931.17 × 490.79
  4. Step 4: Simplify right side
    621.37x = 457,014.84
  5. Step 5: Solve for x
    x = 457,014.84/621.37
  6. Step 6: Final answer
    x = 735.50

Related Problems

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Half scale
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Double scale
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Similar ratio
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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.