Solving ratio problems

The Navodaya Vidyalaya Samiti has successfully conducted the JNVST Class VI Admission Selection Test Every Year with Grownup a huge number of participants. In 2001 there are 5.5 lacks Boy's and Girl Students are Applied for class 5th to 6th standard selection tests. But this year there is more than 31.10 lakh aspirants have reached, this is a very big growth in primary school level entrance test in the country.JNVST Result 2022 The Jawahar Navodaya Vidyalaya (JNV) Samiti concluded the Class VI admission test for the 2022 academic session in April for the Class 6th Admission Selections at 8252 exam centres situated in 561 district headquarter centres across the country. There are 30,46,506 students registered and appeared for the available seats of 51000. Last year 30,10,710 Boys and Girl candidates had registered from all urban and rural areas and this year higher than the previous year.

A class consists of 16 kids, 6 boys and 10 girls.
Emily questioned all the students and discovered that
8 out of 10 girls prefer valentines day over birthdays, but only 2 out of 6 boys prefer valentines day over birthdays.
What is the ratio of children in the class that prefer valentines day over birthdays.

26 (Students) x .46 (46% boys) = approximately 12 boys (11.96)
26 (students) - 12 (boys) = 14 girls

142.

435 - 151 = 284
This subtracts the inequality between girls and boys.

Then the rest are split in half equally.

284 / 2 = 141

Hope this helps. Got any more ;)

The average is 20, it means the total is 60. The sum of ratio is 15 (3+5+7)
Therefore the age of a girl is calculated by multiplying the respective ration with total and dividing by sum of ratio
Age of Eldest girl = 7 x 60 /15 = 28

Hope it helps! Good Luck!
CreativeTECH

If there are 40 total students, and 25 are boys, then (40-25) of them are girls, or 15.
That means the ratio of boys to girls is 25 to 15, or 25/15
This can be simplified by dividing by 5, so the ratio is 5/3

If there are 25 boy in a class of 40 pupils, there are 40 - 25 = 15 girls. The ratio of boys to girls hence is 25:15, or as reduced fraction 5:3 = 1.6666...

Here is your problem pasted again ingluding some of my thoughts. These thoughts and the answers to your questions are in CAPITAL.
There are exactly twelve children in Ryan's class. Only four of the children are boys. THAT MEANS THERE ARE 8 GIRLS. The following questions refer to a time when all the children are present in the class. THAT MEANS THE TOTAL PERSONS IN THE CLASS ARE 12 SINCE THERE IS NO MENTION ABOUT TEACHER. There are no visitors in the class. There might be more than one correct anwer to a question.

1. Which of the lettered statements must be true?
2. Which of the lettered statements cannot be true?
3. Which of the lettered statements could be true or not true?

a. There are twice as many girls as boys in Ryan's class. IS TRUE
b. There are eight more girls than boys in Ryan's class. IS FALSE
c. There are four more girls than boys in Ryan's class. IS TRUE
d. If Ryan is sitting at a table with all the girls, there are exactly nine children at that table. IS TRUE
e. If only three of the boys are standing on their heads, one of the boys is not standing on his head. IS TRUE.

In case of a problem or clarification, don't hesitate to post me a reply.
If you are satisfied, rate my solution with the "thumbs" or (even better) add a testimonial.

Thanks and regards
Please kindly rate this solution
Stelios
direct FixYa link: http://www.fixya.com/users/technical114

The best way to solve this is to develop one or more equations and then solve for the unknown numbers.

I solved this problem twice using different sets of equations to make sure I was right, and here is what I found:

1) I used the equations x + y = 623, and x = (2/3)y. In these equations, x is the number of girls and y is the number of boys.
Substituting the second equation into the first, I get (2/3)y + y = 623.
Adding the left side together I get : (5/3)y = 623.
Dividing both sides by (5/3) I get 373.8.
This means that x (the number of girls) is 249.2.

2) For the second attempt, I developed the equation: 2x+3x=623. Here 2x is the number of girls, and 3x is the number of boys.
Adding the left side I get: 5x = 623.
Dividing both sides by 5 I get: x = 124.6.
This means that the number of girls (2x) is 249.2. Just like in the first method.

But since you can't have a 1/5 of a girl, the answer must be 249 girls.