Home / 621-856.98-345

Finding the Fourth Proportional to 621, 856.98 and 345

Calculator

Solution

The fourth proportional to 621, 856.98 and 345 is: 476.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    621 : 856.98 = 345 : x
  2. Step 2: Convert to fraction form
    621/856.98 = 345/x
  3. Step 3: Cross multiply
    621x = 856.98 × 345
  4. Step 4: Simplify right side
    621x = 295,658.10
  5. Step 5: Solve for x
    x = 295,658.10/621
  6. Step 6: Final answer
    x = 476.10

Related Problems

Find fourth proportional to 310.50, 428.49 and 172.50
Half scale
Find fourth proportional to 1,242, 1,713.96 and 690
Double scale
Find fourth proportional to 622, 858.36 and 346
Similar ratio
Find fourth proportional to 931.50, 1,285.47 and 517.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.