1. Box A contains 50 cents coins and Box B contains 20 cents coins. There are 19 more coins in Box B than in Box A but the amount of money in Box A is $1.30 more than the amount in Box B. How much money is in Box A?
2. A big tank had 890L of water. A small tank had 170L of water. When an equal amount of water was added to both tanks, the big tank had 3 times as much water as the small tank. How much water was added into each tank?
3. Tina had a bag of rice. Her family ate an equal amount of rice each day. After 3 days, she had 4/5 of the rice left. After another 7 days, she had 24 kg of rice left. How much rice was in the bag at first?
4. Mrs Lee sold all her cakes in three days. On the first day, she sold 2/3 of a cake plus 1/3 of a cake. On the second day, she sold 2/3 of the remaining cakes plus 1/3 of a cake. On the third day, she sold 2/3 of the new remainder plus 1/3 of a cake. How many cakes did she sell?
5. The head of a toy dog is 10 cm long. Its tail is as long as its head plus 1/2 the length of its body. The body is as long as the head and the tail together. What is the length of the toy dog?
Originally posted by kkhing:1. Box A contains 50 cents coins and Box B contains 20 cents coins. There are 19 more coins in Box B than in Box A but the amount of money in Box A is $1.30 more than the amount in Box B. How much money is in Box A?
2. A big tank had 890L of water. A small tank had 170L of water. When an equal amount of water was added to both tanks, the big tank had 3 times as much water as the small tank. How much water was added into each tank?
3. Tina had a bag of rice. Her family ate an equal amount of rice each day. After 3 days, she had 4/5 of the rice left. After another 7 days, she had 24 kg of rice left. How much rice was in the bag at first?
4. Mrs Lee sold all her cakes in three days. On the first day, she sold 2/3 of a cake plus 1/3 of a cake. On the second day, she sold 2/3 of the remaining cakes plus 1/3 of a cake. On the third day, she sold 2/3 of the new remainder plus 1/3 of a cake. How many cakes did she sell?
5. The head of a toy dog is 10 cm long. Its tail is as long as its head plus 1/2 the length of its body. The body is as long as the head and the tail together. What is the length of the toy dog?
1. When 19 coins are taken away from Box B, Box A and Box B will have the same amount of coins. The total values of coins in Box A more than Box B will become $1.30+$0.20X19=$5.10
Since each coin in Box A is worth $0.30 more than each coin in Box B, amount of coins in Box A=$5.10/$0.30=17 coins
Hence, amount of money in Box A=17coinsX$0.50=$8.50
2. Draw out a model. You will see that 2 big units + a small unit = 890L, whereas a small unit = 170L. 1 big unit=360L after calculations, and amount of water put in = 1 big unit - 1 small unit=360L-170L=190L
3. Amount of rice at first=15/15. Amount of rice after 3 days=4/5=12/15. Hence, after 7 more days, amount of rice=12/15-7/15=5/15=1/3. Thus,1/3 of the rice is 24kg, and the total amount of rice at first = 24kgX3=72kg.
4. I am sorry, but I don't understand...
5. I don't think algebra should be used for a P6 student, but I am sorry, as I can't think of anything else at the moment. Let the body be x units. The tail=10+1/2x, thus the body=20+1/2x. Since x=20+1/2x, x=40cm. Thus, the head=10cm, the body=40cm, the tail=30cm, and the entire dog=80cm.
Originally posted by TrueHeart:1. When 19 coins are taken away from Box B, Box A and Box B will have the same amount of coins. The total values of coins in Box A more than Box B will become $1.30+$0.20X19=$5.10
Since each coin in Box A is worth $0.30 more than each coin in Box B, amount of coins in Box A=$5.10/$0.30=17 coins
Hence, amount of money in Box A=17coinsX$0.50=$8.50
2. Draw out a model. You will see that 2 big units + a small unit = 890L, whereas a small unit = 170L. 1 big unit=360L after calculations, and amount of water put in = 1 big unit - 1 small unit=360L-170L=190L
3. Amount of rice at first=15/15. Amount of rice after 3 days=4/5=12/15. Hence, after 7 more days, amount of rice=12/15-7/15=5/15=1/3. Thus,1/3 of the rice is 24kg, and the total amount of rice at first = 24kgX3=72kg.
4. I am sorry, but I don't understand...
5. I don't think algebra should be used for a P6 student, but I am sorry, as I can't think of anything else at the moment. Let the body be x units. The tail=10+1/2x, thus the body=20+1/2x. Since x=20+1/2x, x=40cm. Thus, the head=10cm, the body=40cm, the tail=30cm, and the entire dog=80cm.
You can try this for questions similar to question 2 next time:
Big Tank l______l______l_l_____l
Small Tank l_l_____l
Tada : D
Originally posted by Forbiddensinner:You can try this for questions similar to question 2 next time:
Big Tank l______l______l_l_____l
Small Tank l_l_____l
Tada : D
Thank you very much. I will be sure to keep this in mind.
Sorry, some typo errors to Q4, this is the actual question.
4. Mrs Lee sold all her cakes in three days. On the first day, she sold 2/3 of the cake plus 1/3 of a cake. On the second day, she sold 2/3 of the remaining cakes plus 1/3 of a cake. On the third day, she sold 2/3 of the new remainder plus 1/3 of a cake. How many cakes did she sell?
3 cakes in total.. this is so easy..
first day.. 1/3cake left plus 2/3cake left
second day.. remaining 2/3cake from yesterday sold plus new cake 2/3left, yesterday 1/3cake left
third day.. yesterday 2/3cake cake sold plus yesterday 1/3cake sold..
so total is 3 cakes sold..
Originally posted by kkhing:Sorry, some typo errors to Q4, this is the actual question.
4. Mrs Lee sold all her cakes in three days. On the first day, she sold 2/3 of the cake plus 1/3 of a cake. On the second day, she sold 2/3 of the remaining cakes plus 1/3 of a cake. On the third day, she sold 2/3 of the new remainder plus 1/3 of a cake. How many cakes did she sell?
No it is alright, please don't apologise.
For this question, we will have to work backwards.
By selling 2/3 of the new remainder, she will have 1/3 of the new remainder left, and since all the cakes are sold out, 1/3 of the new remainder = 1/3 of a cake. Hence, the new remainder = 1 cake. This also means that 1/3 of the remaining cakes = (1+1/3) cakes. That means the total remaining cakes = 3X(1+1/3) = 4 cakes.
Continuing on, this means that 1/3 of the original cakes = (4+1/3) cakes. Hence number of cakes at first, which will also be the number of cakes she sold, =3X(4+1/3)=13 cakes.
Originally posted by ColdSnowyIce:3 cakes in total.. this is so easy..
first day.. 1/3cake left plus 2/3cake left
second day.. remaining 2/3cake from yesterday sold plus new cake 2/3left, yesterday 1/3cake left
third day.. yesterday 2/3cake cake sold plus yesterday 1/3cake sold..
so total is 3 cakes sold..
Erm, I believe what she means is that Mrs Lee sold all her cakes in three days, not that Mrs Lee has three cakes in all... Cheers.
i make it clearer..
1st day: 1st cake 1/3 left, 2nd cake 2/3 left
2nd day: 2nd cake 2/3 left is sold today, 3rd cake 2/3 left, 1st cake 1/3 left
3rd day: 3rd cake and 1st cake sold
so is 3 cakes
i read wrong lo
didnt know it was so difficult but i can do it one.. but very difficult to explain.. hey any more for me to try?