Answer:
its B
Step-by-step explanation:
I just did it
We can use ratios, in other words, if one part of the photo is changed x times, how many times does the other part change?
We can set up the proportion as :
width 1 : length 1 = width 2 : length 2
20 : 30 = 5 : x
We do inverse multiplication, or multiply the outer with outer and inner with inner (W1 * L2 and L1 * W2)
20*x = 30*5
20x = 150
Divide all by 10
2x = 15
Divide all by 2 to isolate x
x = 15/2
x = 7.5cm
Answer:
7. A
8. C
9. C
10. A
Step-by-step explanation:
You just have to work each one out. This is very simple.
We know that
density=mass/volume
solve for mass
mass=density*volume
step 1
find the area of the garage door in cm²<span>
Area=300*700------> 210000 cm</span>²
step 2
find the volume of the paint
Volume=area*thick
thick=1 mm-----> 0.1 cm
Volume=210000*0.1-----> 21000 cm³
step 3
find the mass
mass=density*volume
density=1.2 g/cm³
volume=21000 cm³
mass=1.2*21000-----> 25200 grams
the answer is
25200 grams
Area of circle = πr²
1075.21 = πr²
1075.21/π = r²
r = √1075.21/π
r = 18.5