3+ (2) 4+ 1 = 12
Good luck
Answer:
10√2
Step-by-step explanation:
5√2³ = 5√8 = 5√(2 x 4) = (2 x 5)√2 = 10√2
the number of elements in the union of the A sets is:5(30)−rAwhere r is the number of repeats.Likewise the number of elements in the B sets is:3n−rB
Each element in the union (in S) is repeated 10 times in A, which means if x was the real number of elements in A (not counting repeats) then 9 out of those 10 should be thrown away, or 9x. Likewise on the B side, 8x of those elements should be thrown away. so now we have:150−9x=3n−8x⟺150−x=3n⟺50−x3=n
Now, to figure out what x is, we need to use the fact that the union of a group of sets contains every member of each set. if every element in S is repeated 10 times, that means every element in the union of the A's is repeated 10 times. This means that:150 /10=15is the number of elements in the the A's without repeats counted (same for the Bs as well).So now we have:50−15 /3=n⟺n=45
There are 20 boys in the class. The ratio is 4:3 so that means 4 out of 7 are boys and 3 out of 7 are girls. Divide 35 by 7 and you get 5. 5 times 4 is 20. 5 times 3 is 15. add them together and you have 35 students in total. So 20 students are boys and 15 students are girls.