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Sedrick Tan

Asked 9 years ago

SG Primary 6 Measurement

This is a P6 questions. Can anyone guide the next step to get the answer

Replies 3

Xavier Sng

Since tank B has half the base area as tank A, for a given volume of water that is removed from tank A and filled into tank B, the height of the water level in tank A drops at half the height increase in tank B. As both tanks are 30 cm in height, it reasons that tank A's water level will have to drop 10 cm while tank B's water level rises by 20cm. Considering water draining from tank A, (80 × 20 × 10)/800 = 20 min OR Consider water filling tank B, (800 × 20)/800 = 20 min (ans)

6 years ago

Sedrick Tan

Thank you.

6 years ago

Xavier Sng

The pleasure is mine. Regards

6 years ago

Sedrick Tan

Asked 9 years ago

SG Primary 6 Measurement

Replies 6

Foong Ling

is the answer 2 mins ?

6 years ago

Xavier Sng

The answer is 20 min,

6 years ago

Sedrick Tan

The correct answer is 20min.

6 years ago

Foong Ling

Can show how? Thanks

6 years ago

Sedrick Tan

Here is the answer by Xavier: Since tank B has half the base area as tank A, for a given volume of water that is removed from tank A and filled into tank B, the height of the water level in tank A drops at half the height increase in tank B. As both tanks are 30 cm in height, it reasons that tank A's water level will have to drop 10 cm while tank B's water level rises by 20cm. Considering water draining from tank A, (80 × 20 × 10)/800 = 20 min OR Consider water filling tank B, (800 × 20)/800 = 20 min (ans)

6 years ago

Xavier Sng

Many thanks, Sedrick.

6 years ago

Vivian Ang

Asked 9 years ago

SG Primary 6 Number and Algebra

Please help on the question below. Thks.

Replies 4

GC Lau

6 years ago

Xavier Sng

Whenever a quantity is transferred from one entity to another, the difference will change by double the quantity. Since there is a net movement of one marble from B to A, the difference in the marbles between A and B must hence change by two marbles. Add that to the difference of two marbles initially, there is a difference of four marbles between A and B in the end. Since box B has only half as many marbles as box A at the end, there must only be 4 marbles in box B and 8 marbles in box A. Return the one marble to box B, box A will have 7 marbles at first.

6 years ago