Home / 290.50-688

Finding the Third Proportional to 290.50 and 688

Calculator

Solution

The third proportional to 290.50 and 688 is: 1,629.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.50 : 688 = 688 : x
  2. Step 2: Convert to fraction form
    290.50/688 = 688/x
  3. Step 3: Cross multiply
    290.50x = 688 × 688
  4. Step 4: Simplify right side
    290.50x = 473,344
  5. Step 5: Solve for x
    x = 473,344/290.50
  6. Step 6: Final answer
    x = 1,629.41

Related Problems

Find third proportional to 145.25 and 344
Half scale
Find third proportional to 581 and 1,376
Double scale
Find third proportional to 293 and 693
Similar ratio
Find third proportional to 435.75 and 1,032
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.