ARITHMETIC-BASIC-1

1. A number when multiplied by 21 is increased by 420. Find the number?

21
20
22

Step-by-Step Solution:
1. Let the unknown number be x. 2. Setup Equation: 21 * x = x + 420 (Multiplied by 21 equals original plus 420). 3. Subtract x from both sides: 20x = 420. 4. Solve for x: 420 / 20 = 21.

2. A number when multiplied by 15 is increased by 196. Find the number?

14
12
16

Step-by-Step Solution:
1. Let the number be x. 2. Setup Equation: 15x = x + 196. 3. Simplify: 14x = 196. 4. Divide: 196 / 14 = 14.

3. A number when multiplied by 9 is increased by 120. Find the number?

10
15
20

Step-by-Step Solution:
1. Equation: 9x = x + 120. 2. Subtract x: 8x = 120. 3. Solve: x = 120 / 8 = 15.

4. A number when multiplied by 11 is increased by 100. Find the number?

10
9
11

Step-by-Step Solution:
1. Equation: 11x = x + 100. 2. Subtract x: 10x = 100. 3. Solve: x = 100 / 10 = 10.

5. A number when multiplied by 5 is increased by 80. Find the number?

18
20
22

Step-by-Step Solution:
1. Equation: 5x = x + 80. 2. Subtract x: 4x = 80. 3. Solve: x = 80 / 4 = 20.