Tutor MathsGuru: Ask me for your burning Maths questions!

[Hifive]

Hi CoffeeCat


Thanks for your explanation.


Hi mathsguru

Thanks for your model and explanation.

Cheers.

[persistent]

A group of people met a party. Each person shook hands with everyone else. Mr Li shook hands with 3 times as many men as women. Mrs Li shook hands 4 times as many men as women. How many men and how many women were there at the party?



…Men…Women
Clue 1…1+3 units…1 unit
Clue 2… 4 parts…1+1 part

1 unit = 1+1 part;
3 units = 3+3 parts

1+3 units = 4 parts
1+3+3 parts = 4 parts
1 part = 1+3 = 4

Ans.
Men = 4 parts = 4 x 4 = 16
Women = 1+1 part = 1 + 4 = 5

[Hifive]

Hi persistent


Thanks for your explanation.

Cheers

[eric2010]

Tanks X and Y are each filled with some water. If water from Tank Y is poured into Tank X unitl the water in Tank X reaches the brim, there will be 8 litres of water left in Tank Y. If water from Tank X is poured into Tank Y until the water in Tank Y reaches the brim, there will be 26 litres of water left in Tank X. The ratio of the volume of Tank X to the volume of Tank Y is 5:3. How many more litres of water are needed to fill both tanks to their brim ?

[ooptimizer]

You need 19 litres to fill X and Y to the brim.

[eric2010]

thx, i need the steps .

[CoffeeCat]

I will solve using algebra. Let the amt of water in tank X & Y be x and y respectively.

Volume of tank Y = x+y -26
volume of tank X = x+ y -8
From here i use v to represent (x+y), because what x and y is wouldn’t matter,.
using the ratio, v-26= (3/5) * (v-8)
5v - 130 = 3v -24
2v= 106
v=53
Total volume of Tank X + Y = 2v - (26+8) = 2v -34 = 72
Water needed = 72 - 53 = 19.

[mathsguru]

eric2010:

Tanks X and Y are each filled with some water. If water from Tank Y is poured into Tank X unitl the water in Tank X reaches the brim, there will be 8 litres of water left in Tank Y. If water from Tank X is poured into Tank Y until the water in Tank Y reaches the brim, there will be 26 litres of water left in Tank X. The ratio of the volume of Tank X to the volume of Tank Y is 5:3. How many more litres of water are needed to fill both tanks to their brim ?

Hi Eric2010,

Here's my solution. Hope you can understand the diagrams...

Cheers,
MathsGuru

http://www.postimage.org/image.php?v=TsIeCbA

[persistent]

Tanks X and Y are each filled with some water. If water from Tank Y is poured into Tank X until the water in Tank X reaches the brim, there will be 8 litres of water left in Tank Y. If water from Tank X is poured into Tank Y until the water in Tank Y reaches the brim, there will be 26 litres of water left in Tank X. The ratio of the volume of Tank X to the volume of Tank Y is 5:3. How many more litres of water are needed to fill both tanks to their brim?



Scenario 1

…Tank X…Tank Y
Before…5 u - A…8 l + A\t\t\t\t
\t\t
…+ A…- A
\t\t
…

After…5 units…8 l
…



Scenario 2

…Tank X…Tank Y
Before…\t26 l + B…\t3 u - B
\t\t
…- B…+ B
\t\t
…

After…26 l…3 units
…


5 u – A = 26 l + B
5 u – 26 l = A + B


8 l + A = 3 u – B
A + B = 3 u – 8 l

5 u – 26 l = 3 u – 8 l
5 u – 3 u = 26 l – 8 l
2 u = 18 l
1 u = 9 l


Ans. A + B = 3 x 9 l – 8 l = 19 l

[persistent]

Tanks X and Y are each filled with some water. If water from Tank Y is poured into Tank X until the water in Tank X reaches the brim, there will be 8 litres of water left in Tank Y. If water from Tank X is poured into Tank Y until the water in Tank Y reaches the brim, there will be 26 litres of water left in Tank X. The ratio of the volume of Tank X to the volume of Tank Y is 5:3. How many more litres of water are needed to fill both tanks to their brim?



Scenario 1

…Tank X…Tank Y
Before…5 u - A…8 l + A\t\t\t\t
\t\t
…+ A…- A
\t\t
…

After…5 units…8 l
…



Scenario 2

…Tank X…Tank Y
Before…\t26 l + B…\t3 u - B
\t\t
…- B…+ B
\t\t
…

After…26 l…3 units
…


5 u – A = 26 l + B
5 u – 26 l = A + B


8 l + A = 3 u – B
A + B = 3 u – 8 l

5 u – 26 l = 3 u – 8 l
5 u – 3 u = 26 l – 8 l
2 u = 18 l
1 u = 9 l


Ans. A + B = 3 x 9 l – 8 l = 19 l