Home / 309.75-680.63

Finding the Third Proportional to 309.75 and 680.63

Calculator

Solution

The third proportional to 309.75 and 680.63 is: 1,495.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.75 : 680.63 = 680.63 : x
  2. Step 2: Convert to fraction form
    309.75/680.63 = 680.63/x
  3. Step 3: Cross multiply
    309.75x = 680.63 × 680.63
  4. Step 4: Simplify right side
    309.75x = 463,250.39
  5. Step 5: Solve for x
    x = 463,250.39/309.75
  6. Step 6: Final answer
    x = 1,495.56

Related Problems

Find third proportional to 154.88 and 340.31
Half scale
Find third proportional to 619.50 and 1,361.25
Double scale
Find third proportional to 312 and 685
Similar ratio
Find third proportional to 464.63 and 1,020.94
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.20) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.