Answer:
18 marbles
Step-by-step explanation:
Step 1
Express the fraction of each type of marble as a function of the total number of marbles as shown;
Let;
total marbles=x
red marbles=3/(3+4)=3/7x
blue marbles=4/7 x
But x=42 marbles
The total number of marbles for each type can be expressed as;
total number of red marbles=fraction of red marbles×total number of marbles
where;
fraction of red marbles=3/7 x
total number of marbles=42
replacing;
total number of red marbles=(3/7)×42=18 marbles
total number of blue marbles=fraction of blue marbles×total number of marbles
where;
fraction of blue marbles=4/7 x
total number of marbles=42
replacing;
total number of blue marbles=(4/7)×42=24 marbles
27 has to be C
I can't see the whole question for 28 and 29
-48a÷ 8 can be written as,

Put a=1 in the above exprression and solve.

Therefore, the solution is -6.
Answer:
a) yes
b) 2560
Step-by-step explanation:
An exponential function has a common ratio between points uniformly spaced. Here, the data points are 10 years apart.
The ratio of the first two values is 4000/5000 = 0.8.
The ratio of the next two values is 3200/4000 = 0.8.
These ratios are the same, so the data is consistent with an exponential function.
The common ratio can be used to predict the next value. The next value is predicted to be ...
3200 × 0.8 = 2560