Sydney’s security company uses security codes that are 2 letters followed by 3 numbers. How many different codes are possible if letters and numbers cannot be repeated?

468,000 different codes

Step-by-step explanation:

The code has first 2 letters and then 3 numbers.

The first letter has 26 possibilities to be filled.

The second letter has 25 possibilities, as one letter is already used.

Then, for the numbers, we have:

The first number has 10 possibilities to be filled.

The second number has 9 possibilities to be filled (one used).

The third number has 8 possibilities to be filled (two used).

So, the total number of different codes is:

26*25*10*9*8 = 468,000 different codes.

u = -(6/7)w

step-by-step explanation:

place all values with 'u' on one side of the equation.

4u + 8w = - 3u + 2w

4u + 3u = 2w - 8w

further simplify the equation by solving the addition and subtraction.

7u = - 6w

make 'u' the independent variable by placing its co-efficient on the right-hand side.

u = - (6/7)w

step-by-step explanation:

659