The order of multiplication does not matter. We can choose to multiply eleven by three or nine to save work.

Multiply eleven with three.

\(\displaystyle 11\times 3 = 33\)

Multiply thirty-three with nine.

\(\displaystyle 33 \times 9\)

Multiply the ones digits.

\(\displaystyle 3\times 9= 27\)

The carryover is the tens place. Multiply the ones digit with the tens digit and add the carryover.

\(\displaystyle 3\times 9 +2 = 29\)

Combine the numbers. The answer is \(\displaystyle 297\).

Multiply the ones digits.

\(\displaystyle 9 \times 8=72\)

The tens place will be the carryover for the next calculation.

Multiply the tens digit of 29 with the eight and add the carryover.

\(\displaystyle 2\times 8 +7 = 16+7 = 23\)

Combine this number with the ones digit of the first calculation.

The answer is:  \(\displaystyle 232\)

Multiply the ones digit of 587 with the eight.

\(\displaystyle 7 \times 8 = 56\)

The tens place is the carryover.

Multiply the tens digit of 587 with the eight and add the carryover.

\(\displaystyle 8\times 8+5 = 69\)

The tens place is the carryover.

Multiply the hundreds digit of 587 with the eight and add the carryover.

\(\displaystyle 5\times 8+6 = 46\)

Combine this number with the ones digits in the other calculations.

The answer is:  \(\displaystyle 4696\)

Multiply the ones digit of 26 with eight.

\(\displaystyle 6\times8=48\)

The tens place is the carryover.

Multiply the tens digit of 26 with eight and add the carryover.

\(\displaystyle 2\times 8 +4 = 16+4 =20\)

Combine this number with the ones digit of the first calculation.

The answer is: \(\displaystyle 208\)

Multiply 91 with the ones digit.

\(\displaystyle 91\times 1 =91\)

Skip a line and multiply 91 with the tens digit.

\(\displaystyle 91 \times 3 = 273\)

Add a zero at the end of this number.

\(\displaystyle 2730\)

Sum this number with the first number we have calculated.

\(\displaystyle 2730+91 =2821\)

The answer is:   \(\displaystyle 2821\)

Multiply the first number with the ones digit of the second number.

\(\displaystyle 15\times 8 = 120\)

Skip a line, and multiply the first number with the tens digit of the second number.

\(\displaystyle 15\times 4= 60\)

We will need to add a zero to the right of this number.

\(\displaystyle 600\)

Add this number with the first number.

\(\displaystyle 600+120 = 720\)

The answer is:  \(\displaystyle 720\)

Adding a negative is the same as subtraction.

\(\displaystyle 13+(-3)=13-3=10\)

Pair the numbers as follows:

\(\displaystyle 2+2000=2,002\)

\(\displaystyle 4+1998=2,002\)

\(\displaystyle 6+1996=2,002\)

...

\(\displaystyle 1,000+1,002=2,002\)

There are 500 such pairs, so adding all of the even integers from 2 to 2,000 is the same as taking 2,002 as an addend 500 times. This can be rewritten as a multiplication.

\(\displaystyle 2,002* 500 = 1,001,000\)

\(\displaystyle (-15)+12+(-4)+1\)

When adding integers first consider the signs of the numbers being added. Then simply work right to left. \(\displaystyle -15+12\rightarrow-3+(-4)\rightarrow-7+1=-6\)

So the answer is \(\displaystyle -6\)

According to the order of operations:

Work any operation in parentheses first - here it would be the addition.

What remains would be an exponent (the squaring), a division, and a subtraction, which, according to the order of operations, would be worked in that order.