Home / 1,306.10-1,959.35-428.34

Finding the Fourth Proportional to 1,306.10, 1,959.35 and 428.34

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Solution

The fourth proportional to 1,306.10, 1,959.35 and 428.34 is: 642.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,306.10 : 1,959.35 = 428.34 : x
  2. Step 2: Convert to fraction form
    1,306.10/1,959.35 = 428.34/x
  3. Step 3: Cross multiply
    1,306.10x = 1,959.35 × 428.34
  4. Step 4: Simplify right side
    1,306.10x = 839,267.98
  5. Step 5: Solve for x
    x = 839,267.98/1,306.10
  6. Step 6: Final answer
    x = 642.58

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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.