Home / 1,315.30-1,973.32-390.86

Finding the Fourth Proportional to 1,315.30, 1,973.32 and 390.86

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Solution

The fourth proportional to 1,315.30, 1,973.32 and 390.86 is: 586.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,315.30 : 1,973.32 = 390.86 : x
  2. Step 2: Convert to fraction form
    1,315.30/1,973.32 = 390.86/x
  3. Step 3: Cross multiply
    1,315.30x = 1,973.32 × 390.86
  4. Step 4: Simplify right side
    1,315.30x = 771,281.01
  5. Step 5: Solve for x
    x = 771,281.01/1,315.30
  6. Step 6: Final answer
    x = 586.39

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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.