Home / 688.50-1,089

Finding the Third Proportional to 688.50 and 1,089

Calculator

Solution

The third proportional to 688.50 and 1,089 is: 1,722.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.50 : 1,089 = 1,089 : x
  2. Step 2: Convert to fraction form
    688.50/1,089 = 1,089/x
  3. Step 3: Cross multiply
    688.50x = 1,089 × 1,089
  4. Step 4: Simplify right side
    688.50x = 1,185,921
  5. Step 5: Solve for x
    x = 1,185,921/688.50
  6. Step 6: Final answer
    x = 1,722.47

Related Problems

Find third proportional to 344.25 and 544.50
Half scale
Find third proportional to 1,377 and 2,178
Double scale
Find third proportional to 691 and 1,092
Similar ratio
Find third proportional to 1,032.75 and 1,633.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.58) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.