630 red marbles
420 yellow marbles
210 purple marbles
because 1260 x 1/2 = 630, 1260 x 1/3 = 420, 1260 x 1/6 = 210
Given:
Consider the equation is:

Some steps of the solution are given.
To find:
The next step of the solution.
Solution:
Step 1: The given equation is:

Step 2: Simplifying right hand side.

Step 3: Simplifying left hand side.

These steps are already given. So, the next step is:
Step 4: Subtracting 3 from both sides.

Therefore, the correct option is (b).
Answer:scales percent error=3.51%
Step-by-step explanation:
P ercent error = Experimental value - Theoretical value /Theoretical value x 100
Theoretical value = 6255 grams
Experimental value ( use of scale ) = 6475grams
Percent error =(6475- 6255)grams / 6255grams x 100
=220/6255 x 100
=3.51%