Answer:
6
Step-by-step explanation:
Cost per item is found by dividing the cost by the number of items. If the woman bought n items for $120, the cost of each item is $120/n. If the woman bought 24 more items, n+24, at the same price, then the cost per item is $120/(n+24). The problem statement tells us this last cost is $16 less than the first cost:
120/(n+24) = (120/n) -16
Multiplying by n(n+24) gives ...
120n = 120(n+24) -16(n)(n+24)
0 = 120·24 -16n^2 -16·24n . . . . . . subtract 120n and collect terms
n^2 +24n -180 = 0 . . . . . . . . . . . . . divide by -16 to make the numbers smaller
(n +30)(n -6) = 0 . . . . . . . . . . . . . . factor the quadratic
The solutions to this are the values of n that make the factors zero: n = -30, n = 6. The negative value of n has no meaning in this context, so n=6 is the solution to the equation.
The woman bought 6 items.
_____
Check
When the woman bought 6 items for $120, she paid $120/6 = $20 for each of them. If she bought 6+24 = 30 items for the same money, she would pay $120/30 = $4 for each item. That amount, $4, is $16 less than the $20 she paid for each item.
Answer:
3^(2/15)
Step-by-step explanation:
Ask in comments if you want.
Answer:
total surface area = 76 sq.cm
Step-by-step explanation:
total surface area of cuboid = 2 ( lb + lh + bh )
( where l is length , b is width and h is height )
so, surface area :
= 2[ (5×4) + (5×2) + (2×4) ]
= 2 [ 20 + 10 + 8 ]
= 2 × 38
= 76 sq.cm
Answer:
Step-by-step explanation:
Answer:
? = 43.8°
Step-by-step explanation:
cos ? = 13/18 = 0.7222
? = 43.8°
