Answer:
Tash scores 40 baskets
Step-by-step explanation:
Rani = R
Layla = L
Tash = T
R = 4L
T = 4L-8
As L + R + T = 100
L + 4L + 4L-8 = 100
Collect like terms
9L - 8 = 100
+ 8 both sides
9L = 108
divide by 9 both sides
L = 108 / 9
L = 12
Now..... T = 4L-8 substitute L with 12
T = 48 - 8
T = 40
So... the radiator has 15 liters of 70% antifreeze.. but needs an 80% antifreeze
well, so, you need to drain some and put some with higher percentage, seems to be, you will end up at the same 15 liters, possible the radiator's capacity, of 80% antifreeze
so, the same amount going out, of 70% is the same amount going in, of 100% antifreeze
now.. let's use the decimal format for the percents, or 70% is 70/100 or 0.7 and so on

so.. let's subtract, from the current solution, 0.7x and add 1x or x, our antifreeze concentration amount, should be 12 though
10.5 - 0.7x + x = 12
solve for "x"
Exact form:
22/13
Mixed number:
1 9/13
14. 6.4 blocks
15. 1.78
16. 7.47