The equation y = 0.25x describes a proportional relationship between x and y. What is the constant of proportionality?

Constant of propotionality is 0.25.

Direct proportionality means that the dependence between the two variable, x and y in this case, is such that the quotient of those two variables is constant.

y/x=0.25 . Quotient of x and y is constant so we can say that x and y are directly proportional.

Step-by-step explanation:

hope i helped :)if not sorry

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)