Home / 445-642

Finding the Third Proportional to 445 and 642

Calculator

Solution

The third proportional to 445 and 642 is: 926.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    445 : 642 = 642 : x
  2. Step 2: Convert to fraction form
    445/642 = 642/x
  3. Step 3: Cross multiply
    445x = 642 × 642
  4. Step 4: Simplify right side
    445x = 412,164
  5. Step 5: Solve for x
    x = 412,164/445
  6. Step 6: Final answer
    x = 926.21

Related Problems

Find third proportional to 222.50 and 321
Half scale
Find third proportional to 890 and 1,284
Double scale
Find third proportional to 447 and 645
Similar ratio
Find third proportional to 667.50 and 963
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.44) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.