Home / 19-91

Finding the Third Proportional to 19 and 91

Calculator

Solution

The third proportional to 19 and 91 is: 435.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    19 : 91 = 91 : x
  2. Step 2: Convert to fraction form
    19/91 = 91/x
  3. Step 3: Cross multiply
    19x = 91 × 91
  4. Step 4: Simplify right side
    19x = 8,281
  5. Step 5: Solve for x
    x = 8,281/19
  6. Step 6: Final answer
    x = 435.84

Related Problems

Find third proportional to 9.50 and 45.50
Half scale
Find third proportional to 38 and 182
Double scale
Find third proportional to 21 and 101
Similar ratio
Find third proportional to 28.50 and 136.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (4.79) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.