What do you mean about his
Hello! For this question, we will have to subtract fractions. In order to do this, we will have to convert the fractions into the same denominator. We do this by finding the LCD of the two numbers. In other words, we find the LCM. The LCM of 5 and 4 is 20. 4/5 converts to 16/20, and 1/4 converts to 5/20. Let's subtract these numbers like we would regular numbers. 6 16/20 - 3 5/20 is 3 11/20. There. Jordan bought 3 11/20 yards more pink ribbon than purple ribbon.
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.
9 x 15 = ( 9 x 9) + (9 x 15)