Home / 646-1,390

Finding the Third Proportional to 646 and 1,390

Calculator

Solution

The third proportional to 646 and 1,390 is: 2,990.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    646 : 1,390 = 1,390 : x
  2. Step 2: Convert to fraction form
    646/1,390 = 1,390/x
  3. Step 3: Cross multiply
    646x = 1,390 × 1,390
  4. Step 4: Simplify right side
    646x = 1,932,100
  5. Step 5: Solve for x
    x = 1,932,100/646
  6. Step 6: Final answer
    x = 2,990.87

Related Problems

Find third proportional to 323 and 695
Half scale
Find third proportional to 1,292 and 2,780
Double scale
Find third proportional to 648 and 1,394
Similar ratio
Find third proportional to 969 and 2,085
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.15) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.