
By: suz (offline) Monday, September 26 2011 @ 08:00 PM CDT (Read 1487 times)



suz 
pls help to solve the following maths prob sum
Need to know steps in solving. thnks in advance! These beads are giving me a headache.
13. Mdm Zhang packed some beads into 14 small boxes and 15 big boxes. There were equal number of beads in each small box and equal number of beads in each big box. Each big box contain 5 more beads than each small box. 3/8 of the beads are packed in the small box. How many beads are there in each small box?
Ans : 9 beads
17. There were some yellow and green beads in container A and B.In container A ratio yellow to green is 7: 2. In container B ratio yellow to green is 5 : 1. there were 6 times as many beads in container A as in container B.
a) what was the ratio of yellow beads in container A to the number of green beads in container B? Give answ in simplest form.
b) after 84 beads were put into container B, the ratio of the number of yellow beads to the number of green beads in container B became 4:5. How many green beads were there in container B at the end?
Ans a) 28:1
b) 100 green beads

Newbie
Registered: 12/31/06 Posts: 5





By: pkrdd (offline) Monday, September 26 2011 @ 11:13 PM CDT



pkrdd 
Q13. solution using variable method
# of small boxes = 14 > 14units
# of big boxes = 15 = 15 small boxes + 15 * 5 > 15 units + 75
ratio of beads in small; big boxes is 3:5 (since 3/8 of total beads are in small boxes)
total beads = 8 parts.= 29u + 75  1
diffrenece of beads between big box & small boxes
5p 3p = 2p = 15u + 75 14u = u + 75
ie., 2p = u + 75
multiply by 4
8p = 4u + 75 * 4 2
Equating 1 & 2
29u + 75 = 4u + 300
25u = 225
u = 9
Ans: Total beads in each small box = 9
===========================================================
Q17. Use similarly variable approach
Container A = yellow : green = 7:2 (total 9 units)
container B = yellow: green = 5:1 (total 6 parts)
total container A: total container B = 6:1
> 6 * 9u = 1 * 6p
> each p = 9u
container B = 5p : p > 45u : 9u
container B total = 45u + 9u = 54u
Container A total = 54u * 6 (6 times container B ) = 324u
Container A yellow = 324u * 7 /9 = 252u
Container B green = 9u
Ans a) ratio of container A yellow : Container B green = 252u : 9u = 28:1
For b) I will post later..need to rethink on my solution as I got different answer

Junior
Registered: 01/11/10 Posts: 16





By: suz (offline) Monday, September 26 2011 @ 11:29 PM CDT



suz 
thank u so much!

Newbie
Registered: 12/31/06 Posts: 5





By: Kevin1991 (offline) Friday, October 28 2011 @ 02:41 PM CDT



Kevin1991 
Y:G
5:1
20:4
After 84 beads were added,
Y:G
4:5
20:25
25u  4u = 21u
21u = 84
25u = 84/21 x 5
= 100.
There might be typing error in the paper. It did not mention which color was added nor did it say it was transferred from box A, too much variables.

Newbie
Registered: 10/09/11 Posts: 3



