Home / 2,128.39-2,938.21-1,420.65

Finding the Fourth Proportional to 2,128.39, 2,938.21 and 1,420.65

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Solution

The fourth proportional to 2,128.39, 2,938.21 and 1,420.65 is: 1,961.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,128.39 : 2,938.21 = 1,420.65 : x
  2. Step 2: Convert to fraction form
    2,128.39/2,938.21 = 1,420.65/x
  3. Step 3: Cross multiply
    2,128.39x = 2,938.21 × 1,420.65
  4. Step 4: Simplify right side
    2,128.39x = 4,174,164.48
  5. Step 5: Solve for x
    x = 4,174,164.48/2,128.39
  6. Step 6: Final answer
    x = 1,961.19

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.