Fraction Words Problem

[drszone]

Folks,

Please shed a light on for 3 math words problem below (Primary 5 math):

1). 5/8 of the Primary 5 pupils in a school travel to school by school bus. 1/6 of the remaining pupils travel to school by car and the rest of the pupils walk to school. 90 fewer pupils walk to school than take the school bus. How many Primary 5 pupils are there together?

2). 3/5 of the cookies were chocolate chip cookies and the rest were butter cookies. After 2/5 of the chocolate chip cookies were sold, there were 24 more butter cookie than chocolate chip cookies. How many cookies were there at first?

3). Tom and Nora shared some sweets. Nora received 3/5 of the sweets. She gave Tom 8 sweets so that both of them had equal number of sweets. How many sweets did Tom and Nora share in all?



Thanks in advance.

 

[Dr.Peterson]

Please follow our guidelines by showing us what you are stuck and what help you need, and some idea of the context of the problems.

If fractions are relatively new to you (and assuming you can't use algebra), you might try making a picture. Mark off 5/8 of a bar as "bus", then 1/6 of the other part (calculate what fraction that is) as ""car", and mark the rest (what fraction is that?) as "walk = 90". Then think about it.

 

[Deleted member 4993]

Folks, Please shed a light on for 3 math words problem below (Primary 5 math):
1). 5/8 of the Primary 5 pupils in a school travel to school by school bus. 1/6 of the remaining pupils travel to school by car and the rest of the pupils walk to school. 90 fewer pupils walk to school than take the school bus. How many Primary 5 pupils are there together?
2). 3/5 of the cookies were chocolate chip cookies and the rest were butter cookies. After 2/5 of the chocolate chip cookies were sold, there were 24 more butter cookie than chocolate chip cookies. How many cookies were there at first?
3). Tom and Nora shared some sweets. Nora received 3/5 of the sweets. She gave Tom 8 sweets so that both of them had equal number of sweets. How many sweets did Tom and Nora share in all?
Thanks in advance.

I'll start you off with problem #2. ... I did not notice the "section" where it was posted - and used algebra !!
2). 3/5 of the cookies were chocolate chip cookies and the rest were butter cookies. After 2/5 of the chocolate chip cookies were sold, there were 24 more butter cookie than chocolate chip cookies. How many cookies were there at first?
What do you need to find in this problem.....How many cookies were there at first
So let:

# of cookies were there at first - = C

What conditions are given to you:

3/5 of the cookies were chocolate chip cookies .................. # of chocolate chip cookies = 3/5 * C

the rest were butter cookies .................. # of butter cookies = C - 3/5 * C = 2/5 * C

# of chocolate chip cookies left after After 2/5 of the chocolate chip cookies were sold = 3/5 * C - 2/5 * 3/5 * C = 9/25 * C

there were 24 more butter cookie than chocolate chip cookies .......... (# of butter cookies) - (# of chocolate chip cookies left) = 24

2/5 * C - 9/25 * C = 24

Solve for C ( and check for reasonableness)

I am afraid that only non-algebra way I can think of to do this problem is to guess and check. Start 100 total cookies.....

 

[HallsofIvy]

Folks,

Please shed a light on for 3 math words problem below (Primary 5 math):

1). 5/8 of the Primary 5 pupils in a school travel to school by school bus. 1/6 of the remaining pupils travel to school by car and the rest of the pupils walk to school. 90 fewer pupils walk to school than take the school bus. How many Primary 5 pupils are there together?

5/8 of the students ride the bus. The "remaining pupils" are 1- 5/8= (8- 5)/8= 3/8 of the students. 1/6 of them walk to school. That is (1/6)(5/8)= 5/48 of the pupils. So a total of 3/8+ 5/48= (18+ 5)/48= 23/48 of the students either ride the bus or come in a car. That leaves 1- 23/48= (48- 23)/48= 25/48 of the students wall to school. The actual number of students who take the bus minus the number who walk is 5/8- 25/48= (30- 25)/48= 5/48 of the total number of students. That is, 5/48 times the total number of students is 90 so the total number of students is 90 divided by 5/48.

2). 3/5 of the cookies were chocolate chip cookies and the rest were butter cookies. After 2/5 of the chocolate chip cookies were sold, there were 24 more butter cookie than chocolate chip cookies. How many cookies were there at first?

3/5 of the cookies were chocolate chip cookies and the rest, 1- 3/5= 2/5 were butter cookies. 2/5 were of the chocolate chip cookies were sold leaving 2/5 as many chocolate chip cookies. So now (2/5)(3/5)= 6/25 of the original number of cookies were chocolate chip cookies. The difference of cookies now is 2/5- 6/25= (10- 6)/25= 4/25 of the original number of cookies is 24. That is 4/25 times the original number of cookies is 24 so the original number of cookies is 24 divided by 4/25.

3). Tom and Nora shared some sweets. Nora received 3/5 of the sweets. She gave Tom 8 sweets so that both of them had equal number of sweets. How many sweets did Tom and Nora share in all?

I've tried to avoid using algebra but I just don't see any way to do this without algebra to clarify! Let the total number of sweets be "N". The Nora got (3/5)N= 3N/5 and Tom got N- 3N/5= 2N/5. After Nora gave Tom 8 sweets she had 3N/5- 8 and Tom had 2N/5+ 8. Those are equal: 3N/5- 8= 2N/5+ 8. Adding 8 to both sides and subtracting 2N/5 from both sides, N/5= 16, N= 5(16)



Thanks in advance.