The sum of Joe's and Sheila's ages is 115. Fourteen years ago, Joe was twice as old as Sheila. How old is Sheila now?

 Sheila today =  yrs old

Step-by-step explanation:

   J + S = 115 v⇒  J = 115 - S

Current Ages                        Ages 14 years ago

 Joe (J) = 115 - S                      J - 14 = 2(S - 14)

 Sheila (S) = S

Substitute J = 115 - S into the "14 years ago" equation

      J    - 14 = 2(S - 14)

(115 - S) - 14 = 2(S - 14)

111 -S = 2S - 28

111 = 3S  - 28

139 = 3S

46 = S

It is odd that the result was not an integer.  I wonder if you meant to type "Joe was twice as old as Sheila is today.  That would change the equation to:

J - 14 = 2S

111 - S = 2S

111 = 3S

37 = S

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.