Home / 73.89-110.82-19.78

Finding the Fourth Proportional to 73.89, 110.82 and 19.78

Calculator

Solution

The fourth proportional to 73.89, 110.82 and 19.78 is: 29.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.89 : 110.82 = 19.78 : x
  2. Step 2: Convert to fraction form
    73.89/110.82 = 19.78/x
  3. Step 3: Cross multiply
    73.89x = 110.82 × 19.78
  4. Step 4: Simplify right side
    73.89x = 2,191.37
  5. Step 5: Solve for x
    x = 2,191.37/73.89
  6. Step 6: Final answer
    x = 29.66

Related Problems

Find fourth proportional to 36.94, 55.41 and 9.89
Half scale
Find fourth proportional to 147.77, 221.63 and 39.55
Double scale
Find fourth proportional to 74.89, 112.31 and 20.78
Similar ratio
Find fourth proportional to 110.83, 166.22 and 29.66
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.