4. there are 25 students in a college math class. the mean age of 15 students is 20 years. themean age of the remaining 10 students of theclass is 24 years. what is the mean age of all thestudents in the class?

22

The mean is the middle; the middle of 20 and 24 is 22

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.