Answer:
a=9
Step-by-step explanation:
a^3 = 729
Taking the cube root of each side
a^3 ^(1/3) = 729^ (1/3)
a = 9
$27
2.65 x 2 (since he has to go both to and from work each day) = $5.30
Add the daily cost of the water bottle (1.45) to make his total cost for one day, which is 6.75
Multiply this number by 4 (because he goes 4 days a week) to get $27 for one week.
Given:
The price of bananas can be determined by the equation P=0.25n, where P is the price and n is the number of bananas.
To find:
The constant of proportionality
Solution:
We have,
...(i)
where P is the price and n is the number of bananas.
Price P is directly proportional to the number of bananas. So,

...(ii)
Where, k is the constant of proportionality.
On comparing (i) and (ii), we get

Therefore, the constant of proportionality is 0.25.