9 students
30% ends up being .3%, multiply .3% by 30 students which equals 9.
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
Answer:
about 9 pounds, 7 ounces
Step-by-step explanation:
5 ounces per week
for 4 weeks
= 5 x 4 = 20 ounces gained thought these 4 weeks
Now add
8 Pounds, 3 ounces + 20 ounces = 9 pounds, 7 ounces
Answer:
Shorter leg = 2.5 ft.
Longer leg = 6.5 ft.
Step-by-step explanation:
a^2 + b^2 = c^2
Because the hypotenuse = 7 ft, a^2 + b^2 = 49
To represent the two legs, we can use x and x+4.
x^2 + (x+4)^2 = 49
Simplifying this equation using FOIL gives us 2x^2 + 8x - 33 = 0.
Then, using the quadratic formula, we find that x = 2.5.
Thus, the shorter leg is 2.5 ft. and, when 4 is added, the longer leg is 6.5 ft.
Umm im pretty sure d= -3x im not to sure
