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Finding the Fourth Proportional to 661.02, 912.51 and 495.78

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Solution

The fourth proportional to 661.02, 912.51 and 495.78 is: 684.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.02 : 912.51 = 495.78 : x
  2. Step 2: Convert to fraction form
    661.02/912.51 = 495.78/x
  3. Step 3: Cross multiply
    661.02x = 912.51 × 495.78
  4. Step 4: Simplify right side
    661.02x = 452,404.21
  5. Step 5: Solve for x
    x = 452,404.21/661.02
  6. Step 6: Final answer
    x = 684.40

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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.