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Finding the Fourth Proportional to 661.60, 992.40 and 621.10

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Solution

The fourth proportional to 661.60, 992.40 and 621.10 is: 931.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.60 : 992.40 = 621.10 : x
  2. Step 2: Convert to fraction form
    661.60/992.40 = 621.10/x
  3. Step 3: Cross multiply
    661.60x = 992.40 × 621.10
  4. Step 4: Simplify right side
    661.60x = 616,379.64
  5. Step 5: Solve for x
    x = 616,379.64/661.60
  6. Step 6: Final answer
    x = 931.65

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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.