Home / 1,638-2,457-422

Finding the Fourth Proportional to 1,638, 2,457 and 422

Calculator

Solution

The fourth proportional to 1,638, 2,457 and 422 is: 633

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638 : 2,457 = 422 : x
  2. Step 2: Convert to fraction form
    1,638/2,457 = 422/x
  3. Step 3: Cross multiply
    1,638x = 2,457 × 422
  4. Step 4: Simplify right side
    1,638x = 1,036,854
  5. Step 5: Solve for x
    x = 1,036,854/1,638
  6. Step 6: Final answer
    x = 633

Related Problems

Find fourth proportional to 819, 1,228.50 and 211
Half scale
Find fourth proportional to 3,276, 4,914 and 844
Double scale
Find fourth proportional to 1,639, 2,458.50 and 423
Similar ratio
Find fourth proportional to 2,457, 3,685.50 and 633
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.