Answer:
78
Step-by-step explanation:
Given that:
First day (a) = 1
1 more pebble every subsequent day than the previous day
Tn = a + (n - 1)d
d = common difference ; difference between pebbles in two successive days = 1
n = nth day
At the end of the 12th day;
Tn = a + (n - 1)d
T(12) = 1 + (12 - 1) 1
T(12) = 1 + 11
T(12) = 12
Appling the sun if arithmetic progression formula : Sum of AP:
n/2 (a + Tn)
n = number of terms
12/2 (1 + 12)
6(13)
= 78
Answer:
B and D
Step-by-step explanation:
A difference of squares has the form a² - b²
4p² - 9 = (2p)² - 3² ← is a difference of squares
q² - 36 = q² - 6² ← is a difference of squares
Answer:
b^20/a^12
Step-by-step explanation:
b to the power of 20 over a to the power of 12
There would be 35 rulers.
In order to solve this, use cross multiplication.
6/10 = 21/x -----> cross multiply
10*21 = 6*x
210 = 6x
35 = x
