What is the first term if term 15 is -67 and term 21 is -97?
1 answer:
Answer:
3
Step-by-step explanation:
The n th term of an arithmetic sequence is
= a +(n - 1)d
where a is the first term and d the common difference
Given the fifteenth term is - 67, and term 21 is - 97, then
a + 14d = - 67 → (1)
a + 20d = - 97 → (2)
Subtract (1) from (2) term by term
6d = - 30 ( divide both sides by 6 )
d = - 5
Substitute d = - 5 into (1)
a + 14(- 5) = - 67
a - 70 = - 67 ( add 70 to both sides )
a = 3
Thus the first term is 3
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The mean, median and mode are measures of central tendency, that is they tend to indicate the location middle of the data
Required values;
(a) The performance for the week for Park Street
- Revenue is <u>Q₂ < $7,500 < Q₃</u>
- The sales for the week is better than <u>72.91%</u> of all sales
The performance for the week for Bridge Road
- Revenue; <u>Q₂ < $7,100 < Q₃</u>
- The sale for the week is better than <u>59.87%</u> of all sales
(b) The mean is <u>$3611</u>
The median is $<u>3,600</u>
The standard deviation is $<u>3250</u>
The Interquartile range is $<u>6075</u>
Reason:
The table of values that maybe used to find a solution to the question is given as follows;
(a) Park Street revenue = $7,500
Bridge Road's revenue = $7,100
The two stores sold close to but below the 75th percentile
Bridge Road revenue;
The z-score is given as follows;
From the Z-Table, we have;
The percentile= 0.7291
- Therefore, the sale for the week for Park Street is better than <u>72.91%</u> of all the sales
Park Street revenue;
The z-score is given as follows;
From the Z-Table, we have;
The percentile = <u>0.5987</u>
- Therefore, the sale for the week is better than <u>59.87 %</u> of all the sales
(b) Given that the operating cost is $3,000, frim which we have;
The subtracted value is subtracted from the mean and median to find the new value
Profit = The revenue - Cost
New mean = 6611 - 3000 = 3611
- The new mean = <u>$3,611</u>
The new median = 6600 - 3000 = 3600
- The new median = <u>$3,600</u>
The standard deviation and the interquartile range remain the same, therefore, we have;
- The standard deviation = <u>$3,580</u>
The interquartile range = 9675 - 3600 = 6075
- The interquartile range = <u>6075</u>
Learn more here:
Answer:
y = x - 4
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Rearrange 3x - 2y = - 6 into this form
Subtract 3x from both sides
- 2y = - 3x - 6 ( divide all terms by - 2 )
y = x + 3 ← in slope- intercept form
with slope m =
• Parallel lines have equal slopes, hence
y = x + c ← partial equation of parallel line
To find c substitute (4, 2) into the partial equation
2 = 6 + c ⇒ c = 2 - 6 = - 4
y = x - 4 ← equation of parallel line