Pr 6 (fractions) problem

• likeyou

  9 May 10, 21:50

  Hi Everybody, I need help for the fractions. I am having nitemare teaching my son pr 6. Plse help me with this.

   

  1) A box contains green, red, blue and yellow buttons. 36% of the buttons are green. The red buttons are 1/3 the number of green buttons. There are twice as many blue buttons as red buttons and 56 more yellow buttons than blue buttons.

   

  a. How many green buttons are there in the box?

  b. How may more green buttons than yellow buttons are there in the box?

   

  2) Roslinda's monthly pcket money was 3/5 of sheela's monthly pockey money. Roslinda's expenditure was 7/12 of Sheela's expenditure. Roslinda's monthly pockey money was 3/4 of Sheela's expenditure.

   

  a. Find the ratio of Roslinda's saving to Sheela's saving.

  b. If Roslinda saved $11.20, how much more pocket money did Sheela have than Roslinda?

   

  +++++++++++++++++++++++++

   

  Hi Everybody

   

  I tried to use model but I am unable to derive the answer at all.

  Please teach me how.

  Thanks.

   

  @LikeYou

• TTFU

  9 May 10, 22:09

  .

• SBS261P

  9 May 10, 22:10

  red buttons 12%

  blue buttons 24%

  yellow buttons = 28%

  4% of total number of buttons = 56

  therefore number of green buttons = 9 x 56 = 504

  difference between green and yellow = 2 x 56 = 112

• TTFU

  9 May 10, 22:11

  .

• SBS261P

  9 May 10, 22:13

  Roslinda's monthly pcket money was 3/5 of sheela's monthly pockey money
  Roslinda's monthly pockey money was 3/4 of Sheela's expenditure

  so Sheela spend 4/5 of her money.

  If we look at the problem in this way - we express how much roslinda got in terms of sheela.

  Then Roslinda spend 7 /12 x 4/5 = 7/15 of sheela's money.

  Since Roslinda originally gt 3/5 of sheela's money, she gt 2/15 left.

  In the end, Sheela left 1/5 of her money, and Roslinda has 2/15 of Sheela's money.

  So ratio is 2 : 3

• SBS261P

  9 May 10, 22:14

  then since 2/15 of sheela's money is $11.20,

  difference between sheela's pocket money and roslinda's pocket money = $11.20 x (2/5 divide by 2/15) = $11.20 x 3 = $33.60

• SBS261P

  9 May 10, 22:17

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  S |_|_|_|_|_|_|_|_|_|_|_|_|_|_|_|

  sheela spend 12 units and roslinda spend 7 / 12 x 12 = 7 units

  after they spend

  sheela gt 3 left and roslinda gt 2 left.

   

• likeyou

  9 May 10, 22:49

  Hi Everybody

   

  Thanks for your help.

  I just wonder how you know how to solve this type of problems!

  I do until I scream like a mad dog!!!

   

  Thanks bro and sis for your help.

  Thanks a million.

   

  @LikeYou

• SBS261P

  9 May 10, 23:01

  haha i happen to be a relief teacher now so thankfully i'm still in touch with math problem... if nt i think also gone case! haha no problem, it's always like that one la, son and daughter go for exam is always the parents kan chiong first! ^_^

• -StarDust-

  10 May 10, 09:35

  Nowadays pri school already so hard.