Home / 1,405.40-2,108.30-431.32

Finding the Fourth Proportional to 1,405.40, 2,108.30 and 431.32

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Solution

The fourth proportional to 1,405.40, 2,108.30 and 431.32 is: 647.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,405.40 : 2,108.30 = 431.32 : x
  2. Step 2: Convert to fraction form
    1,405.40/2,108.30 = 431.32/x
  3. Step 3: Cross multiply
    1,405.40x = 2,108.30 × 431.32
  4. Step 4: Simplify right side
    1,405.40x = 909,351.96
  5. Step 5: Solve for x
    x = 909,351.96/1,405.40
  6. Step 6: Final answer
    x = 647.04

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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.