27 A shop sells packs of black pens, packs of red pens and packs of green pens.
There are
4 pens in each pack of black pens
5 pens in each pack of red pens
6 pens in each pack of green pens
On Monday,
= 7:3:4
number of packs
of black pens sold
:
number of packs
of red pens sold
number of packs
of green pens sold
A total of 268 pens were sold.
Work out the number of red pens sold.

answer:   the paragraph proof is mentioned below.

step-by-step explanation:

given: in a δxwy where

such that, ∠wzx ≅ ∠yzx and zw≅zy

we have to prove that: segment zx is a perpendicular bisector of segment wy.

prove: since, zw≅zy ⇒ ∠wzy is a supplementary angle.

then, ∠wzy= 180°

⇒∠wzx + ∠yzx = 180° ( because xz divides ∠wzy into two parts)

but, ∠wzx ≅ ∠yzx ( given)

⇒∠wzy+∠wzy=180° ( by substitution)

⇒2∠wzy=180°

⇒∠wzy=90°

⇒∠wzy=∠yzx =90°

therefore, xz⊥wy where wz=zy

⇒zx is a perpendicular bisector of wy.

your answer is b.

1,333 cubic feet  

and i know this one is right.