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Finding the Fourth Proportional to 774.13, 1,068.30 and 420.05

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Solution

The fourth proportional to 774.13, 1,068.30 and 420.05 is: 579.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    774.13 : 1,068.30 = 420.05 : x
  2. Step 2: Convert to fraction form
    774.13/1,068.30 = 420.05/x
  3. Step 3: Cross multiply
    774.13x = 1,068.30 × 420.05
  4. Step 4: Simplify right side
    774.13x = 448,738.08
  5. Step 5: Solve for x
    x = 448,738.08/774.13
  6. Step 6: Final answer
    x = 579.67

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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.