Question 1

This extra challenge has frozen the two brain cells I had to rub together, and fried them at the same time, which I did not know was possible. There's simply not enough information to make an informed, rational decision. I mean, who's writing these challenges? 10 out of 10 for style... I think it has something to do with overhead costs and distance to travel, but I just can't sort it out with any clarity.

Accepted Answer

The expression 2 + 5r for the total cost of r roses means $5 per rose plus a constant $2 fee for the entire purchase.  If the number of roses is doubled (for example, 6 roses instead of 3 roses), only the cost of the roses without the fee is doubled, but the $2 fee is not doubled to $4.  So doubling the number of roses comes $2 short of doubling the total cost.

Algebraically, the total cost of 2r roses is 2 + 5(2r) = 2 + 10r dollars.
However, twice the total cost of r roses would be 2(2 + 5r) = 2(2) + 2(5r) = 4 + 10r dollars.
So once again, we see that doubling the number of roses comes $2 short of doubling the total cost.

Have a blessed, wonderful day!

Question 2

the extra challenge is making me loose my brain cells

Accepted Answer

gurl its not that hard

Question 3

how do you find the value of the muffins and cakes? it doesn't give enough info?

Accepted Answer

It gives all the info you need.
We have the expression:
*2m+10c*
Where *m* are muffins and *c* are cakes.

the question is : _How much money does the dessert store make from selling *three* muffins and *four* cakes?_

So *m* = 3 and *c* = 4
Now just plug muffins and cakes into the expression *2m+10c*
2(3) + 10(4) or 2*3+10*4, both are the same thing

Now do the multiplication first and it becomes:
6 + 40
= 46

$46 dollars for 3 muffins and 4 cakes

Question 4

can you explain 100+20(51/4)

Accepted Answer

100+20(5 1/4)
Follow order of operations rules - PEMDAS:
You must multiply 1st.
-- Change 5 1/4 into an improper fraction = 21/4
-- Multiply: 20 (21/4) = 20/1 * 21/4 = 5 (21) = 105

Your expression is now: 100+105
Add the 2 numbers and you'll have your answer.

Question 5

What grade is everyone going into? 
I'm 6th.

Accepted Answer

I'm in 5th

Question 6

What does the 2 signify in the equation 2+5r?

Accepted Answer

Here 2 is just 2! It's a constant, which means that it doesn't change. 5r can change depending on what r is. So, if we let r = 4, then 2+5r becomes 2+5(4), which becomes 2+20= 22. If r had been a different number we would get a different answer. But 2 is always going to get added to 5r, regardless of what r is. Hope this helps.

Question 7

Cam has 32 dollars. How many roses can he afford to buy?
Assume that he wants to buy as many roses as he can. The answer is he can buy 6 roses for $32 but I do not understand why that is the answer.

Accepted Answer

If he buys 6 roses, the cost (from the formula in the problem) is 2 + 5r = 2 + 5(6) = 32.

Question 8

What does it mean mathematically if you "plug something in"?

Accepted Answer

It's called "substitution".  You replace one item with another of equal value.

Question 9

I literally don't understand anything why is the first answer 10 and not 53 that makes no sense if I were to multiply 5 by ten that would be 50 and if I add 3 that would be 53 this makes no sense what so ever

Accepted Answer

1st Question:  What is Sal finding when he uses t=10?
The problem tells you "t" is the number of tickets.  And, it tells you that the expression calculates the cost of tickets.  So, if Sal is using t=10, he is find the cost of 10 tickets.  The question didn't ask you to find the cost.  It asked you what the end result would represent.

Also, the last option (the number of tickets that you can buy for $53) assumes that you know the cost and you don't know the number of tickets.  The tickets is the given value.

Hope this helps.

Question 10

I can't explain the extra challenge. I just used the formula that they said to use.

Accepted Answer

The explanation is that the cost of 6 roses is not the same as the double the cost of 3 roses because after you multiply 6 by 5 you also have to add an extra 2 because that will make it 7r. After adding the cot will change no matter what. So if they had only told us 5r and do not add 2 then it would be the double of 3, but they also said to add 2 which makes this different from 3.

Hope this helps :)

Hope this helps :)

Number of roses $(r)$ ‍	Cost $(2 + 5 r)$ ‍
$3$ ‍	$17$ ‍
$6$ ‍	Your answer should be an integer, like $6$ ‍ a simplified proper fraction, like $3 / 5$ ‍ a simplified improper fraction, like $7 / 4$ ‍ a mixed number, like $1 3 / 4$ ‍ an exact decimal, like $0.75$ ‍ a multiple of pi, like $12 pi$ ‍ or $2 / 3 pi$ ‍
$9$ ‍	Your answer should be an integer, like $6$ ‍ a simplified proper fraction, like $3 / 5$ ‍ a simplified improper fraction, like $7 / 4$ ‍ a mixed number, like $1 3 / 4$ ‍ an exact decimal, like $0.75$ ‍ a multiple of pi, like $12 pi$ ‍ or $2 / 3 pi$ ‍

6th grade

Course: 6th grade > Unit 6

Evaluating expressions with variables word problems

Reflection question

Let's try a practice problem!

Challenge problem

Extra challenge

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