Home / 690-939.75

Finding the Third Proportional to 690 and 939.75

Calculator

Solution

The third proportional to 690 and 939.75 is: 1,279.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    690 : 939.75 = 939.75 : x
  2. Step 2: Convert to fraction form
    690/939.75 = 939.75/x
  3. Step 3: Cross multiply
    690x = 939.75 × 939.75
  4. Step 4: Simplify right side
    690x = 883,130.06
  5. Step 5: Solve for x
    x = 883,130.06/690
  6. Step 6: Final answer
    x = 1,279.90

Related Problems

Find third proportional to 345 and 469.88
Half scale
Find third proportional to 1,380 and 1,879.50
Double scale
Find third proportional to 692 and 942
Similar ratio
Find third proportional to 1,035 and 1,409.63
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.