Home / 163.20-243.54-139.20

Finding the Fourth Proportional to 163.20, 243.54 and 139.20

Calculator

Solution

The fourth proportional to 163.20, 243.54 and 139.20 is: 207.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    163.20 : 243.54 = 139.20 : x
  2. Step 2: Convert to fraction form
    163.20/243.54 = 139.20/x
  3. Step 3: Cross multiply
    163.20x = 243.54 × 139.20
  4. Step 4: Simplify right side
    163.20x = 33,900.77
  5. Step 5: Solve for x
    x = 33,900.77/163.20
  6. Step 6: Final answer
    x = 207.73

Related Problems

Find fourth proportional to 81.60, 121.77 and 69.60
Half scale
Find fourth proportional to 326.40, 487.08 and 278.40
Double scale
Find fourth proportional to 164.20, 245.03 and 140.20
Similar ratio
Find fourth proportional to 244.80, 365.31 and 208.80
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.