Home / 73.20-109.20-66.36

Finding the Fourth Proportional to 73.20, 109.20 and 66.36

Calculator

Solution

The fourth proportional to 73.20, 109.20 and 66.36 is: 99.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.20 : 109.20 = 66.36 : x
  2. Step 2: Convert to fraction form
    73.20/109.20 = 66.36/x
  3. Step 3: Cross multiply
    73.20x = 109.20 × 66.36
  4. Step 4: Simplify right side
    73.20x = 7,246.51
  5. Step 5: Solve for x
    x = 7,246.51/73.20
  6. Step 6: Final answer
    x = 99.00

Related Problems

Find fourth proportional to 36.60, 54.60 and 33.18
Half scale
Find fourth proportional to 146.40, 218.40 and 132.72
Double scale
Find fourth proportional to 74.20, 110.69 and 67.36
Similar ratio
Find fourth proportional to 109.80, 163.80 and 99.54
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.