A group of friends is addressing wedding invitations. Casey can address 23 envelopes in one hour, Anne can address 45 envelopes in two hours, and Paula can address 61 envelopes in three hours. About how long will it take them to address 310 envelopes?

"4.71" is the correct answer.

Step-by-step explanation:

As we know, 45 envelopes addressed in 2 hours then,

⇒  

and, 45 in 3 hours,

⇒  

Now by adding all together, we get

⇒  

⇒  

and multiply it by "4.71", we get

⇒  

⇒  

Round it "310".

So that "4.71" is the right answer.

fist on the left goes with the third on the right. second on the left goes with the fourth on the right. third on the left goes with the second on the right. the fourth on the left goes with first on the right

9 sandwiches per hour

step-by-step explanation:

when we have a rate, we want a 1 in the denominator

27/3 = 9

27 sandwiches/ 3 hours = 9 sandwiches/hour