Any value of x must be less than -5 for n to be negative. (x<-5)
Let X = the 29% alloy and Y = the 60% alloy.
They want a total of 80kg, so you have X +Y = 80
Rewrite that to get X = 80-Y
You also want 0.20X + 0.60Y = 0.52(80)
Replace X with 80-y:
0.20(80-y) + 0.60y = 0.52(80)
Simplify:
16 - 0.20y + 0.60y = 41.6
Combine like terms:
16 +0.40y = 41.6
Subtract 16 from each side:
0.40y = 25.6
Divide both sides by 0.40
y = 25.6 / 0.40
y = 64
Now you have Y replace y with 80 in X = 80-Y
X = 80 - 64
X = 16
They need 64 Kg of the 60% alloy and 16 Kg of the 20% alloy.
Answer:
A
Step-by-step explanation:
To find the volume we do 2 * 1.25 * 1.5 (i rewrote the fractions as decimals) which is 3.75 or 3 and 3/4 cubic inches.
Answer:
1 / 8², B
Step-by-step explanation:
8 / 8³
8³ = 8*8*8
So, the equation can also be written as:
8 / 8*8*8
divide the numerator and denominator by 8.
1 / 8*8
This is equal to:
1 / 8²
The answer is B.
Answer:
254 cm² (to 3 s.f.)
Step-by-step explanation:
Area of shaded region
= area of large circle -area of smaller circle
Radius of large circle= 15cm
Radius of smaller circle= 12cm
Area of shaded region
= π(15²) -π(12²)
= 225π -144π
= 81π
= 81(3.14)
= 254.34
= 254 cm² (3 s.f.)