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Finding the Fourth Proportional to 665.70, 918.18 and 455.72

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Solution

The fourth proportional to 665.70, 918.18 and 455.72 is: 628.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.70 : 918.18 = 455.72 : x
  2. Step 2: Convert to fraction form
    665.70/918.18 = 455.72/x
  3. Step 3: Cross multiply
    665.70x = 918.18 × 455.72
  4. Step 4: Simplify right side
    665.70x = 418,428.40
  5. Step 5: Solve for x
    x = 418,428.40/665.70
  6. Step 6: Final answer
    x = 628.55

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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.