Question

the tens digit exceeds the units digit by 3. If the units digit is r what is the value of the number ?The next even integer that is larger than 2n, if 2n is an even integer.

Answer 1

a) we know that:

the tens digit exeeds the units digit by 3, then if we have two digits

ab.

and b, the digit for units is equal to r.

then a, the digit for tens, is equal to r + 3.

Then, if r = 4, we have that the digit for tens is r + 3 = 7

and the number is 74.

b) if n is an integer, then we know that 2*n is an even number.

Now, the next even number is always 2 units away, then the next even number to 2*n is:

2*n + 2 = 2*(n + 1)