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Finding the Fourth Proportional to 781.80, 1,079 and 502.35

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Solution

The fourth proportional to 781.80, 1,079 and 502.35 is: 693.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.80 : 1,079 = 502.35 : x
  2. Step 2: Convert to fraction form
    781.80/1,079 = 502.35/x
  3. Step 3: Cross multiply
    781.80x = 1,079 × 502.35
  4. Step 4: Simplify right side
    781.80x = 542,035.65
  5. Step 5: Solve for x
    x = 542,035.65/781.80
  6. Step 6: Final answer
    x = 693.32

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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.