How to do this question plz

no

Step-by-step explanation:

you can start by setting the equation to "?+ ? + ? = 57"

this is because we know for sure that all of the marbles combined is 57

then you can say that b is a variable to show how many marbles Becky has

so now your equation is "? + ? + b = 57"

we know that Chris has two times as many marbles as Becky, so that is like saying "Chris = b + b" this is the same as 2b

we can put that into the equation and get "? + 2b + b = 57"

Dan has seven more marbles than Chris so its like saying "Dan = 2b + 7"

we can put this into the equation and get "2b + 7 + 2b + b = 57"

you solve this equation to get b = 10

this means that Becky has 10 marbles, Chris has 20, and Dan has 27

(we know this by plugging in the value of b into the equations for Dan and Chris)

Now back to the original question: Dan said that he can give some marbles to Becky in order to make them all have the same amount of marbles, is Dan right?

the answer is no

Dan can only give seven marbles to Becky because if he gives seven marbles to Becky, Dan and Chris will have the same amount, 20. But Becky will only have 17.

but which class are u may know that first

the radius is 2 times the diameter.

step-by-step explanation: