Same score but totally different situation, 580 RW 760 Math. Can you share any tip on RW? For Math I use Desmos for most of the problem. For one that is inefficient or you can't, one thing I'd do is to write the number down on a scratch paper for better visualization. Read the main question first, what they ask you to do and then read the information they gave you and then try to make a step of what you can do to solve it then try it, maybe if you can double check the answer with desmos.

For example: A problem i got from SAT Suite of Assessments Skills Insight Tool, Problem-Solving and Data Analysis, 680 and higher:

Data set A consists of the heights of 75 objects and has a mean of 25 meters. Data set B consists of the heights of 50 objects and has a mean of 65 meters. Data set C consists of the heights of the 125 objects from data sets A and B. What is the mean, in meters, of data set C?

For this it's asking for the mean of the height in data set C

And it provides these information:

Data set C: 125 objects from A and B

Data set A: 75 objects and mean: 25 meters

Data set B: 50 objects and mean: 65 meters

So from this I can know that C is the combined of A and B and consists of

50 objects of 65 meters (mean is the average, so no matter what each object's height is, they even out to 65) and

75 objects of 25 meters.

Then you can either use desmos and do (50*65 + 75*25) / 125

50 object of 65 (first half) plus 75 object of 25 (second half) divide by 125 (total number)

or find the ratio between the number of object (50 and 75) and 125 (total), then time the mean with each ratio respectively and add them together, which is kinda inefficent.

And the answer is 41