Answer:
30
Step-by-step explanation:
20+2(3*7 - 4*4)
20+2(21-16)
20+2*5
20+10
30
Answer:
100
Step-by-step explanation:
We have the sum of first n terms of an AP,
Sn = n/2 [2a+(n−1)d]
Given,
36= 6/2 [2a+(6−1)d]
12=2a+5d ---------(1)
256= 16/2 [2a+(16−1)d]
32=2a+15d ---------(2)
Subtracting, (1) from (2)
32−12=2a+15d−(2a+5d)
20=10d ⟹d=2
Substituting for d in (1),
12=2a+5(2)=2(a+5)
6=a+5 ⟹a=1
∴ The sum of first 10 terms of an AP,
S10 = 10/2 [2(1)+(10−1)2]
S10 =5[2+18]
S10 =100
This is the sum of the first 10 terms.
Hope it will help.
Answer:
425
Step-by-step explanation:
3/4 = 9/12
2/3 = 8/12
9/12 - 8/12 = 1/12
So Johnny ran for 1/12 of an hour longer than Angie.