Home / 1,428.36-2,139.63-988.50

Finding the Fourth Proportional to 1,428.36, 2,139.63 and 988.50

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Solution

The fourth proportional to 1,428.36, 2,139.63 and 988.50 is: 1,480.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,428.36 : 2,139.63 = 988.50 : x
  2. Step 2: Convert to fraction form
    1,428.36/2,139.63 = 988.50/x
  3. Step 3: Cross multiply
    1,428.36x = 2,139.63 × 988.50
  4. Step 4: Simplify right side
    1,428.36x = 2,115,024.26
  5. Step 5: Solve for x
    x = 2,115,024.26/1,428.36
  6. Step 6: Final answer
    x = 1,480.74

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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.