Home / 312-643.13

Finding the Third Proportional to 312 and 643.13

Calculator

Solution

The third proportional to 312 and 643.13 is: 1,325.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    312 : 643.13 = 643.13 : x
  2. Step 2: Convert to fraction form
    312/643.13 = 643.13/x
  3. Step 3: Cross multiply
    312x = 643.13 × 643.13
  4. Step 4: Simplify right side
    312x = 413,609.77
  5. Step 5: Solve for x
    x = 413,609.77/312
  6. Step 6: Final answer
    x = 1,325.67

Related Problems

Find third proportional to 156 and 321.56
Half scale
Find third proportional to 624 and 1,286.25
Double scale
Find third proportional to 314 and 647
Similar ratio
Find third proportional to 468 and 964.69
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.06) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.