The best way to multiply complicated problems mentally* is to break them into chunks.
Start with 20 times 8 to get 160, and then 8 times 5 to get 40. Add these together to get 200. 200 times 3 is 600, and 20 times 200 is 4000. Add these together to get your final answer, 4600.
In other words 8 x 20 + 8 x 5 = 200 200 x 3 + 200 x 20 = 4600
*I assumed you meant mentally, because otherwise you'd just multiply longhand, multiplying two of the three numbers and then multiplying their product with the third.
210 pieces
Step-by-step explanation:
First, you need to figure out how many pieces a single machine can cut in a minute, so you need to divide 105 by 3, which gets you 35 pieces per minute.
Next, since we know there are 6 machines, and one machine canncut 35 pieces per minute, we can the figure out how many pieces all 6 cutting machines can cut in 1 minute. You would do this by making an equation such as this:

The x represents the total number of pieces cut by all 6 machines in one minute.
Next, since we now have an equation, we can go ahead and solve it. We would multiply 35 by 6, which would get us 210 pieces per minute that can be cut by all six machines
Answer:
D
Step-by-step explanation:
We know









<h3>Option b is coreect</h3>