Home / 1,370.40-1,890-1,021.92

Finding the Fourth Proportional to 1,370.40, 1,890 and 1,021.92

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Solution

The fourth proportional to 1,370.40, 1,890 and 1,021.92 is: 1,409.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,370.40 : 1,890 = 1,021.92 : x
  2. Step 2: Convert to fraction form
    1,370.40/1,890 = 1,021.92/x
  3. Step 3: Cross multiply
    1,370.40x = 1,890 × 1,021.92
  4. Step 4: Simplify right side
    1,370.40x = 1,931,428.80
  5. Step 5: Solve for x
    x = 1,931,428.80/1,370.40
  6. Step 6: Final answer
    x = 1,409.39

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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.