A meter is 100 cm. A ball of string has 10m of string, and you multiply 10m by 100cm, you get 1,000cm. Then you multiply 40cm by 2, and you get 80cm, or two lengths of string. Then you multiply 35, which is half of 70, by 80, and that is 2,800 cm.
2,800÷40cm=70
And 100cm=1m.
The teacher will therefore need 28 balls of string.
3a + a - 15 = 225 . your substituting b(a-15) into the first equation. <span />
Speed = distance / time
30 = d / 2.5
30 * 2.5 = d
75 = d
40 = d / 1.875
40 * 1.875 = d
75 = d
50 = d / 1.5
50 * 1.5 = d
75 = d
60 = d / 1.25
60 * 1.25 = d
75 = d
24 = 75 / time
time = 75/24
time = 3.125 hours
1. The formula for the area of a rectangle is:
A=LxW
L: The lenght of the rectangle (L=2W).
W: The width of the rectangle.
2. Let's substitute L=2W into the formula A=LxW:
A=LxW
A=2WxW
A=2W²
3. When we clear "W", we obtain:
W²=A/2
W=√(A/2)
4. We already know the value of "A", so:
W=√(50 ft²/2)
W=√(25 ft²)
W=5 ft
5. Now, we must substitute the value of "W", into L=2W:
L=2W
L=2(5 ft)
L=10 ft
6. The perimeter of a rectangle is:
P=2L+2W
7. We know the value of "L" and "W", therefore:
P=(2x10 ft)+(2x5 ft)
P=20 ft+10 ft
P=30 ft
W<span>hat is the perimeter of the porch?
</span>
The answer is: 30 ft
