Answer:
36 stickers
Step-by-step explanation:
7 erasers in each bag
7 x 3 bags = 21 erasers total
57 - 21 =36
Equation:
Total items = 7x + 12y
Answer: $-84
Step-by-step explanation:
The answer is B, divide the rate by the unit to simplify
Answer:
Option C
Step-by-step explanation:
Given that for a random sample of 20 houses selected from a city showed that the mean size of these houses is 1880 square feet with a standard deviation of 320 square feet.
X, the sizes of houses is Normal
Hence sample mean will be normal with
Mean = 1880
and std dev = 
For 90% confidence interval critical value for t with degree of freedom 19 is
1.328
Confidence interval upper bound
= mean + margin of error
= 
Option C is right
Answer:
m∠CBD = m∠CDB ⇒ proved
Step-by-step explanation:
Let us solve the question
∵ AB ⊥ BD ⇒ given
→ That means m∠ABD = 90°
∴ m∠ABD = 90° ⇒ proved
∵ ED ⊥ BD ⇒ given
→ That means m∠EDB = 90°
∴ m∠EDB = 90° ⇒ proved
∵ ∠ABD and ∠EDB have the same measure 90°
∴ m∠ABD = m∠EDB ⇒ proved
∵ m∠ABD = m∠ABC + m∠CBD
∵ m∠EDB = m∠EDC + m∠CDB
→ Equate the two right sides
∴ m∠ABC + m∠CBD = m∠EDC + m∠CDB
∵ m∠ABC = m∠EDC ⇒ given
→ That means 1 angle on the left side = 1 angle on the right side, then
the other two angles must be equal in measures
∴ m∠CBD = m∠CDB ⇒ proved