Answer:
16
Step-by-step explanation:
because it's g of 7 use the third equation.
(7+1)(7-5) = 8x2 = 16
X - number of 5 c stamps,
y - number of 15 c stamps,
z - number of 25 c stamps.
The system:
x + y + z = 160
y = 3 x
0.05 x + 0.15 y + 0.25 z = 25 / * 100
-------------------------------------------------
x + y + z = 160
y = 3 x
5 x + 15 y + 25 z = 2500 / : 5
----------------------------------------
x + 3 x + z = 160
x + 3 y + 5 z = 500
-------------------------
4 x + z = 160 / * ( - 1 )
10 x + 5 z = 500 / : 5
------------------------------
- 4 x - z = - 160
+
2 x + z = 100
-------------------------
- 2 x = - 160
x = 30, y = 90
z = 160 - 120 = 40
Answer:
- 30 of 5 c stamps,
- 90 of 15 c stamps,
- 40 of 25 c stamps.
Answer:
11/16 pounds each
Step By Step Explanation:
Change the mixed fraction to improper fraction
2 3/4 = 11/4
Divide the answer by 4
11/4 ÷ 4 = 11/16
Each friend gets 11/16 pounds