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Finding the Fourth Proportional to 811.20, 1,210.88 and 714

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Solution

The fourth proportional to 811.20, 1,210.88 and 714 is: 1,065.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.20 : 1,210.88 = 714 : x
  2. Step 2: Convert to fraction form
    811.20/1,210.88 = 714/x
  3. Step 3: Cross multiply
    811.20x = 1,210.88 × 714
  4. Step 4: Simplify right side
    811.20x = 864,564.75
  5. Step 5: Solve for x
    x = 864,564.75/811.20
  6. Step 6: Final answer
    x = 1,065.78

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.