The correct answer is B. Hope it helps!
Answer:
15 grams
Step-by-step explanation:
There is a 50 gram chocolate bar that contains 30% cocoa. So we are basically finding 30% of 50. We break 30 into 3*10 and 50 into 5*10. 5*3 = 15.
Therefore, there are 15 grams of cocoa in the chocolate bar.
I hope this helps.
Answer:
- <u>120 pens and 200 pencils.</u>
<u></u>
Explanation:
You can set a system of two equations.
<u>1. Variables</u>
<u />
- x: number of pens
- y: number of pencils
<u>2. Cost</u>
- <em>each pen costs</em> $1, then x pens costs: x
- <em>each pencil costs</em> $0.5, then y pencil costs: 0.5y
- Then, the total cost is: x + 0.5y
- The cost of the whole purchase was $ 220, then the first equation is:
x + 0.5y = 220 ↔ equation (1)
<u>3. </u><em><u>There were 80 more pencils than pens</u></em>
Then:
pencils = 80 + pens
↓ ↓
y = 80 + x ↔ equation (2)
<u>4. Solve the system</u>
i) Substitute the equation (2) into the equation (1):
ii) Solve
iii) Substitute x = 120 into the equation (2)
Solution: 120 pens and 200 pencils ← answer
Note that a squared pyramid has a square base & 4 equal triangles.
To find the lateral the lateral area you calculate the area of the 4 equal triangles and to find the surface area (total Area) you add the area of the base:
Area of each triangle = side (5) x slant (9) and you divide by 2
==>Aera of 1 triangle = (9x5)/2 = 45/2 & for the 4 triangles
Lateral area = (45/2) x 4 = 90 in²
Now the base area (square) = 5 x 5= 25 in²
so the surface area = 90+25 = 115 in² (answer a)
