Home / 657.75-678

Finding the Third Proportional to 657.75 and 678

Calculator

Solution

The third proportional to 657.75 and 678 is: 698.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.75 : 678 = 678 : x
  2. Step 2: Convert to fraction form
    657.75/678 = 678/x
  3. Step 3: Cross multiply
    657.75x = 678 × 678
  4. Step 4: Simplify right side
    657.75x = 459,684
  5. Step 5: Solve for x
    x = 459,684/657.75
  6. Step 6: Final answer
    x = 698.87

Related Problems

Find third proportional to 328.88 and 339
Half scale
Find third proportional to 1,315.50 and 1,356
Double scale
Find third proportional to 660 and 680
Similar ratio
Find third proportional to 986.63 and 1,017
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.03) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.