Home / 1,938.80-2,908.14-640.28

Finding the Fourth Proportional to 1,938.80, 2,908.14 and 640.28

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Solution

The fourth proportional to 1,938.80, 2,908.14 and 640.28 is: 960.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,938.80 : 2,908.14 = 640.28 : x
  2. Step 2: Convert to fraction form
    1,938.80/2,908.14 = 640.28/x
  3. Step 3: Cross multiply
    1,938.80x = 2,908.14 × 640.28
  4. Step 4: Simplify right side
    1,938.80x = 1,862,009.34
  5. Step 5: Solve for x
    x = 1,862,009.34/1,938.80
  6. Step 6: Final answer
    x = 960.40

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1.5x scale

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.