Home / 1,420.08-2,130.36-640.09

Finding the Fourth Proportional to 1,420.08, 2,130.36 and 640.09

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Solution

The fourth proportional to 1,420.08, 2,130.36 and 640.09 is: 960.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.08 : 2,130.36 = 640.09 : x
  2. Step 2: Convert to fraction form
    1,420.08/2,130.36 = 640.09/x
  3. Step 3: Cross multiply
    1,420.08x = 2,130.36 × 640.09
  4. Step 4: Simplify right side
    1,420.08x = 1,363,616.81
  5. Step 5: Solve for x
    x = 1,363,616.81/1,420.08
  6. Step 6: Final answer
    x = 960.24

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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.