Home / 70-78.50

Finding the Third Proportional to 70 and 78.50

Calculator

Solution

The third proportional to 70 and 78.50 is: 88.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    70 : 78.50 = 78.50 : x
  2. Step 2: Convert to fraction form
    70/78.50 = 78.50/x
  3. Step 3: Cross multiply
    70x = 78.50 × 78.50
  4. Step 4: Simplify right side
    70x = 6,162.25
  5. Step 5: Solve for x
    x = 6,162.25/70
  6. Step 6: Final answer
    x = 88.03

Related Problems

Find third proportional to 35 and 39.25
Half scale
Find third proportional to 140 and 157
Double scale
Find third proportional to 72 and 81
Similar ratio
Find third proportional to 105 and 117.75
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.