Tutor MathsGuru: Ask me for your burning Maths questions!

[ozora]

MathIzzzFun:

ozora:

Need help. Unable to comprehend \" with the same amount of money?\" Does it mean $90?

How to solve?
Jane bought some pens at $90. If she was given a discount of 20% on her purchase, she would be able to buy 6 more pens with the same amount of money. Find the usual price of 1 pen.

Hi

Discount of 20% = $90 x 0.2 = $ 18
1 pen = $ 18/6 = $3 = 80% of original price

So original price = 10/8 x $3 = $ 3.75 / pen

cheers.

oic
thanks

[andante]

MathIzzzFun:

andante:

Hi,

pls help to solve the following question WITHOUT using simultaneous equation.

There was a total of 2400 red, blue and green marbles in Box A and Box B at first. The number of marbles in Box A was twice the number of marbles in Box B. In Box A, The number of red marbles is 25% of the total number of blue and green marbles. The number of blue and green marbles in Box B is 60% of the total number of marbles in Box B. After transferring some marbles between each other, 25% of the marbles in Box A and 75% of marbles in Box B were red. How many marbles were there in Box A after the change?

Hi

hope this helps

http://www.flickr.com/photos/62167097@N02/5997248173/in/photostream

cheers.

Hi,
Thanks for the solution but I dont really understand why 2400/ 4 ?
why 4 ? how to group as 4 ? and 640-600/2 why 2 ?

[MathIzzzFun]

andante:

MathIzzzFun:

[quote=\"andante\"]Hi,

pls help to solve the following question WITHOUT using simultaneous equation.

There was a total of 2400 red, blue and green marbles in Box A and Box B at first. The number of marbles in Box A was twice the number of marbles in Box B. In Box A, The number of red marbles is 25% of the total number of blue and green marbles. The number of blue and green marbles in Box B is 60% of the total number of marbles in Box B. After transferring some marbles between each other, 25% of the marbles in Box A and 75% of marbles in Box B were red. How many marbles were there in Box A after the change?

Hi

hope this helps

http://www.flickr.com/photos/62167097@N02/5997248173/in/photostream

cheers.

Hi,
Thanks for the solution but I dont really understand why 2400/ 4 ?
why 4 ? how to group as 4 ? and 640-600/2 why 2 ?[/quote]Hi

After transfer,

Box A = @ @ @ @
Box B = * * * *
Total in Box A + Box B = 2400,
so @ + * = 2400 / 4 = 600 (there are 4 groups of \"@ + *\" in Box A & Box B)

25% of Box A and 75% of Box B are red,
so @ + * * * = 640,

since @ + * = 600, * * = 640-600, * = (640-600)/2 = 20

cheers.

[andante]

MathIzzzFun:

andante:

[quote=\"MathIzzzFun\"]Hi,

pls help to solve the following question WITHOUT using simultaneous equation.

There was a total of 2400 red, blue and green marbles in Box A and Box B at first. The number of marbles in Box A was twice the number of marbles in Box B. In Box A, The number of red marbles is 25% of the total number of blue and green marbles. The number of blue and green marbles in Box B is 60% of the total number of marbles in Box B. After transferring some marbles between each other, 25% of the marbles in Box A and 75% of marbles in Box B were red. How many marbles were there in Box A after the change?

Hi

hope this helps

http://www.flickr.com/photos/62167097@N02/5997248173/in/photostream

cheers.

Hi

After transfer,

Box A = @ @ @ @
Box B = * * * *
Total in Box A + Box B = 2400,
so @ + * = 2400 / 4 = 600 (there are 4 groups of \"@ + *\" in Box A & Box B)

25% of Box A and 75% of Box are red,
so @ + * * * = 640,

since @ + * = 600, * * = 640-600, * = (640-600)/2 = 20

cheers.[/quote]Thank you very much

[MathIzzzFun]

andante:

MathIzzzFun:

Hi

After transfer,

Box A = @ @ @ @
Box B = * * * *
Total in Box A + Box B = 2400,
so @ + * = 2400 / 4 = 600 (there are 4 groups of \"@ + *\" in Box A & Box B)

25% of Box A and 75% of Box are red,
so @ + * * * = 640,

since @ + * = 600, * * = 640-600, * = (640-600)/2 = 20

cheers.

Thank you very much

u r welcome

cheers.

[jtparent]

Hi,

need ur assistance in the below q:

Brain has some 50cent, 20cent & 10cent coin. 60% of his coins are 50cent & 20cent. The number of his 10cent coin is 75% that of his 50cent coins. If he has $16 worth of 50cent coins,what percentage of the value of all his coins is the value of 20cent coins.Give your ans correct to 2 decimal place.

[Angel25]

Beatrice arranged some beads in 15 short rows and 14 long rows. there were 36 more beads in each long row than each short row. Beatrice used 70% of the beads she had to arrange the beads in long rows while the rest of the beads were arranged in short rows. How many beads were there in each short row?


steps and explanations pls

[MathIzzzFun]

Angel25:

Beatrice arranged some beads in 15 short rows and 14 long rows. there were 36 more beads in each long row than each short row. Beatrice used 70% of the beads she had to arrange the beads in long rows while the rest of the beads were arranged in short rows. How many beads were there in each short row?


steps and explanations pls

hi

http://i54.tinypic.com/wch5c7.jpg\">

cheers.

[MathIzzzFun]

jtparent:

Hi,

need ur assistance in the below q:

Brain has some 50cent, 20cent & 10cent coin. 60% of his coins are 50cent & 20cent. The number of his 10cent coin is 75% that of his 50cent coins. If he has $16 worth of 50cent coins,what percentage of the value of all his coins is the value of 20cent coins.Give your ans correct to 2 decimal place.

Hi

ratio of number of 10cent coins : 50cent coins = 3:4 = 6u : 8u
ratio of number of 10cent coins : 50cent & 20 cent coins = 2:3 = 6u : 9u
so, ratio of number of 10cent coins: 50cent coins : 20cent coins = 6u:8u:1u

ratio of value of 10cent coins: 50cent coins : 20cent coins
= 6ux1:8ux5:1ux2
= 6u:40u:2u

So, value of 20cent coins as percentage of value of all the coins
= 2u/(40u+6u+2u)x100% = 1/24 x 100% =4.17% (to 2 decimal place)

cheers.

[jtparent]

MathIzzzFun:

jtparent:

Hi,

need ur assistance in the below q:

Brain has some 50cent, 20cent & 10cent coin. 60% of his coins are 50cent & 20cent. The number of his 10cent coin is 75% that of his 50cent coins. If he has $16 worth of 50cent coins,what percentage of the value of all his coins is the value of 20cent coins.Give your ans correct to 2 decimal place.

Hi

ratio of number of 10cent coins : 50cent coins = 3:4 = 6u : 8u
ratio of number of 10cent coins : 50cent & 20 cent coins = 2:3 = 6u : 9u
so, ratio of number of 10cent coins: 50cent coins : 20cent coins = 6u:8u:1u

ratio of value of 10cent coins: 50cent coins : 20cent coins
= 6ux1:8ux5:1ux2
= 6u:40u:2u

So, value of 20cent coins as percentage of value of all the coins
= 2u/(40u+6u+2u)x100% = 1/24 x 100% =4.17% (to 2 decimal place)

cheers.

hi
thanks for the solution. is this the only way to solve this q? btw what type of method do you use to solve this?