Home / 12,639-18,958.50-3,405

Finding the Fourth Proportional to 12,639, 18,958.50 and 3,405

Calculator

Solution

The fourth proportional to 12,639, 18,958.50 and 3,405 is: 5,107.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    12,639 : 18,958.50 = 3,405 : x
  2. Step 2: Convert to fraction form
    12,639/18,958.50 = 3,405/x
  3. Step 3: Cross multiply
    12,639x = 18,958.50 × 3,405
  4. Step 4: Simplify right side
    12,639x = 64,553,692.50
  5. Step 5: Solve for x
    x = 64,553,692.50/12,639
  6. Step 6: Final answer
    x = 5,107.50

Related Problems

Find fourth proportional to 6,319.50, 9,479.25 and 1,702.50
Half scale
Find fourth proportional to 25,278, 37,917 and 6,810
Double scale
Find fourth proportional to 12,640, 18,960 and 3,406
Similar ratio
Find fourth proportional to 18,958.50, 28,437.75 and 5,107.50
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.