Home / 1,113.21-1,670.45-420.36

Finding the Fourth Proportional to 1,113.21, 1,670.45 and 420.36

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Solution

The fourth proportional to 1,113.21, 1,670.45 and 420.36 is: 630.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,113.21 : 1,670.45 = 420.36 : x
  2. Step 2: Convert to fraction form
    1,113.21/1,670.45 = 420.36/x
  3. Step 3: Cross multiply
    1,113.21x = 1,670.45 × 420.36
  4. Step 4: Simplify right side
    1,113.21x = 702,179.91
  5. Step 5: Solve for x
    x = 702,179.91/1,113.21
  6. Step 6: Final answer
    x = 630.77

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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.