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Finding the Fourth Proportional to 830.30, 1,145.39 and 515.75

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Solution

The fourth proportional to 830.30, 1,145.39 and 515.75 is: 711.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.30 : 1,145.39 = 515.75 : x
  2. Step 2: Convert to fraction form
    830.30/1,145.39 = 515.75/x
  3. Step 3: Cross multiply
    830.30x = 1,145.39 × 515.75
  4. Step 4: Simplify right side
    830.30x = 590,726.59
  5. Step 5: Solve for x
    x = 590,726.59/830.30
  6. Step 6: Final answer
    x = 711.47

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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.