Question

An oil company fills 1 over 10 of a tank in 1 over 5 hour. At this rate, which expression can be used to determine how long will it take for the tank to fill completely?

1 over 5 ⋅ 10 hours
1 over 10 ⋅ 5 hours
1 over 5 ⋅ 1 over 10 hour
5 ⋅ 10 hours

Answer 1

I think its B

Answer 2

after time t, what is the portion of filled tank?

Answer 3

B

Answer 4

Is it C or B

Answer 5

we can write this proportion:
\[\Large \frac{1}{{10}}:\frac{1}{5} = 1:t\]
now use the fundamental property of proportions to find the value of t

Answer 6

O so i say D

Answer 7

what do you get?

Answer 8

are you sure?

Answer 9

Is it D or A lol

Answer 10

hint:
solving that proportion for t, we get:
\[\Large t = \left( {\frac{1}{5} \times 1} \right) \times 10\]

Answer 11

so, what is the right option?

Answer 12

A

Answer 13

In general if we have the subsequent proportion:
\[\Large a:b = c:t\]
then, applying the fundamental property of proportions, we get:
\[\Large t = \frac{{b \times c}}{a}\]

Answer 14

in our case, we can write:
\[\Large t = \left( {\frac{1}{5} \times 1} \right) \times 10 = \frac{1}{5} \times 10\]

Answer 15

so, what is the right option?

Answer 16

@Michele_Laino. A

Answer 17

that's right!