Three sevenths of the students in class 4C are boys.There are 4 more girls than boys.How many boys are there in the class

Answer 1

I know what the answer is, but I can't tell you the mathematical way to get that answer.

I started with multiples of 7. 28 seemed a logical number of students in a class.

3/7 are boys, then (3/7) * 28 = 12

12 + 4 = 16

12 are boys and 16 are girls

12 + 16 = 28

Answer 2

total number of students ---- x
number of boys ----- (3/7)x
number of girls ------(4/7)x

(4/7)x = (3/7)x + 4
times 7, the LCD
4x = 3x + 28
x = 28

boys: (3/7)(28) = 12
girls = 28-12 = 16

Answer 3

What is the probability of selecting a purple marble and then a white marble?
What is the probability of selecting two white marbles?
Is there a greater chance of selecting two white marbles in a row or two purple marbles in a row? Show your work.

What is the probability of selecting a purple marble and then a white marble?
What is the probability of selecting two white marbles?
Is there a greater chance of selecting two white marbles in a row or two purple marbles in a row? Show your work.

What is the probability of selecting a purple marble and then a white marble?
What is the probability of selecting two white marbles?
Is there a greater chance of selecting two white marbles in a row or two purple marbles in a row? Show your work.

What is the probability of selecting a purple marble and then a white marble?
What is the probability of selecting two white marbles?
Is there a greater chance of selecting two white marbles in a row or two purple marbles in a row? Show your work.