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Finding the Fourth Proportional to 677.12, 1,015.60 and 312.20

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Solution

The fourth proportional to 677.12, 1,015.60 and 312.20 is: 468.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    677.12 : 1,015.60 = 312.20 : x
  2. Step 2: Convert to fraction form
    677.12/1,015.60 = 312.20/x
  3. Step 3: Cross multiply
    677.12x = 1,015.60 × 312.20
  4. Step 4: Simplify right side
    677.12x = 317,070.32
  5. Step 5: Solve for x
    x = 317,070.32/677.12
  6. Step 6: Final answer
    x = 468.26

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.