Answer:
750 grams of 60% alloy
Step-by-step explanation:
Define x = amount of 60% alloy and y = amount of 20% alloy
Equating the amounts of gold:
0.6x+0.2y = 1000(0.5)
Since there must be 1000 grams total:
x+y = 1000
Writing the 2 resulting equations together:
0.6x + 0.2y = 500
x + y = 1000
Multiply the first equation by 5:
3x + y = 2500
x + y = 1000
Subtracting the 2nd equation from the 1st:
2x = 1500
x = 750
Answer: 750 grams of 60% alloy
300-30.3=269.7 because you barrow from 3 in 300 because you can't round into 0 and that equalled 7 and than you do 9-0=9 and there's 009.7 than you do 9-3=6 and that's 069.7 and you do 2-0=2 and there's 269.7
Answer:
B
Step-by-step explanation:
A has 2 it crosses the x axis 2x
B Has 1.
C has 2
D has none since it never touched the x axis
The first digit can be any one of the numbers 2-9 That a total of 8 numbers.
The next 6 digits can be any permutation of 6 from the numbers 0 to 9.
(10 numbers)
nPr = n! / r!
so here we have 10P6 = 10! / 6! = 10*9*8*7 = 5040
So final answer is 8 * 5040 = 40,320
