Home / 1,991.79-2,749.98-1,428.18

Finding the Fourth Proportional to 1,991.79, 2,749.98 and 1,428.18

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Solution

The fourth proportional to 1,991.79, 2,749.98 and 1,428.18 is: 1,971.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,991.79 : 2,749.98 = 1,428.18 : x
  2. Step 2: Convert to fraction form
    1,991.79/2,749.98 = 1,428.18/x
  3. Step 3: Cross multiply
    1,991.79x = 2,749.98 × 1,428.18
  4. Step 4: Simplify right side
    1,991.79x = 3,927,461.48
  5. Step 5: Solve for x
    x = 3,927,461.48/1,991.79
  6. Step 6: Final answer
    x = 1,971.83

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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.