Answer:
The savings of Sid and Tim will be in 17:9 in 6 weeks.
Step-by-step explanation:
Initial savings of Sid = £ 13
Initial savings of Tim = £ 0
For each successive week Sid saved = £ 3.5
For each successive week Tim saved = £ 3
Let us assume that after "x weeks" the amounts of Sid and Tim are in ratio 17:9.
If Sid saves £ 3.5 in one week, in x weeks he will £ 3.5x. Since he had £ 13 initially, total amount he would have in x weeks will be £ (13 + 3.5x)
If Time saves £ 3 one week, in x weeks he will save £ 3x. Since, he didn't have any money initially, in x weeks he would have saved £ 3x
The ratio of their savings in x weeks would be 17:9
So,
Sid's saving : Tim's saving = 17 : 9
Using the values of expressions, we get:

This means, the savings of Sid and Tim will be in 17:9 in 6 weeks.
3y = -2x + 2
y = x + 4 (Substitute the y)
3(x + 4) = -2x + 2 (Distribute)
3x + 12 = -2x + 2 (Add 3 to both sides)
+3x +3x
------------------------------------------
12 = 1x + 2 (Subtract 2 from both sides)
-2 - 2
------------------------
10 = 1x (Divide by 1 on both sides)
10/1 = 1x/1
x = 10
This is your x-coordinate
150 more male bats need to be tagged
if you want 2/5 to be female you divide the 260 (<160+100) by 2 to get 130
then you multiply 130 by 3 to get the total amount of male bats that need to be tagged
130*3=390
then you subtract 240 from the 390 to find out how many more bats need to be tagged
390-240=150
Answer:
Total amount Silas and Raja has at first = $252
Step-by-step explanation:
Let,
Amount Silas had = x
Amount Raja had = y
According to given statement;
x = 3y Eqn 1
x-84 = y+42 Eqn 2
Putting value of x from Eqn 1 in Eqn 2
3y - 84 = y+42
3y-y = 42+84
2y = 126
Dividing both sides by 2

Putting y = 63 in Eqn 1
x = 63(3)
x = 189
Total amount they had = 189 + 63 = $252
Hence,
Total amount Silas and Raja has at first = $252