Answer:
234
Step-by-step explanation:
We want to find the summation from n = 2 to n = 10 of the equation -4 + 5n.
We can use the summation formula:
, where a1 is the first term, 
is the last term, and n is the number of terms
Here, we can say the first term occurs when n = 2:
-4 + 5n
-4 + 5 * 2 = -4 + 10 = 6
The last term will be when n = 10:
-4 + 5n
-4 + 5 * 10 = -4 + 50 = 46
The number of terms is just 10 - 2 + 1 = 9 terms.
Substitute these in:
Thus, the answer is 234.
a. 28 * 63
28 (60) + 28 (3) or 20 (60) +20 (3) + 8 (60) + 8 (3)
1680 + 84=1764 1200 / 60 +480 +24=1764
b. 17(59)
17 (50) + 17 (9) or 10 (50) + 10 (9) + 7 (50) +7 (3)
850 + 153=1003 500 + 90 + 63 =1003
c.458 (15)
458 (10) +458 (5) or 10 (400) + 10 (50) + 10 (8) + 5 (400) +5 (50) + 5 (8)
4580 +2290 = 6870 400 + 500 + 80 + 2000 + 250 + 40 = 6870
My work is kinda confusing but hope it helped
Answer:
for the 1st year she earned 160 so for 3 years she will earn $480
