372 books will be there and 20 shelves can hold 360 books it will need 21 shelves
Answer:
x=150
y=240
Step-by-step explanation:
*Use simultaneous equation solving
1.Label your equations
x+y=390......1
2x+4y=1260......2
*make one of the unknowns subject of formula, to form equation 2
x=390-y.....3
*sub.3 into 2
2(390-y)+4y=1260
780-2y+4y=1260
2y+780=1260
y=240
sub. y into 3
x=390-y
x=390-240
x=150
Answer:
A
Step-by-step explanation:
Let's set hours as h.
We know that she earns 5 dollars an hour. If, for example, she worked 2 hours, she would have earned 2*5=10 dollars. This is 5h.
Next, we know that she got 186 dollars in tips. Tips means that she earned extra money, so therefore, the equation is 5h+186, or A