Answer:
57.885
Step-by-step explanation:
For such calculations a probability calculator is very helpful. The one in the attachment shows the 87th percentile to be 57.885.
___
A table of the standard normal distribution will tell you the 87th percentile corresponds to a z-value of 1.12639. Then the X value is ...
X = Zσ +μ = 1.12639(7) +50 = 57.885
The answer is 45 degrease
Answer:

Step-by-step explanation:
<u>Step 1: Convert words into numbers
</u>

<u>Step 2: Multiply
</u>


<u>Step 3: Divide
</u>


Answer: 
S = sally C = Chris J = Joe
sally is one year older than 3 times the age of joe, so
s = 3j + 1
chris is 5 years younger than 6 times the age of jo, so
c = 6j - 5
sally and chris are the same age so
s = c so
3j + 1 = 6j - 5
-3j -3j
1 = 3j - 5
+5 +5
6 = 3j or
3j = 6
3j/3 = 6/3
j = 2
check
s = c
3(2) +1 = 6(2) - 5
6 + 1 = 12 - 5
7 = 7 correct✅
Answer:
15:10
Step-by-step explanation:
Method 1: 5 lots of 3:2 →5 × (3:2) = (5×3) : (5×2) = 15:10
Method 2: 3/2 × 1 → 3/2 ×5/5 = 3×5 2×5= 15:10
boys: 15
girls: 10