Home / 51-80

Finding the Third Proportional to 51 and 80

Calculator

Solution

The third proportional to 51 and 80 is: 125.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    51 : 80 = 80 : x
  2. Step 2: Convert to fraction form
    51/80 = 80/x
  3. Step 3: Cross multiply
    51x = 80 × 80
  4. Step 4: Simplify right side
    51x = 6,400
  5. Step 5: Solve for x
    x = 6,400/51
  6. Step 6: Final answer
    x = 125.49

Related Problems

Find third proportional to 25.50 and 40
Half scale
Find third proportional to 102 and 160
Double scale
Find third proportional to 53 and 83
Similar ratio
Find third proportional to 76.50 and 120
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.