first off, let's convert the mixed fraction to improper fraction, bearing in mind that a/b is really a decimal a ÷ b, and (a ÷ b ) * 100 is the percent format.
Answer:
12.01% discount
Step-by-step explanation:
R2499-100%
R2199-?
=R2199/R2499×100%
=87.99
100%-87.99%=12.01%
Answer:
14) y = 81
15) n = 6
Step-by-step explanation:
14)
54:30 = y:45
cross multiply: 45(54) = 30y, so y = 81
15)
6:3 = 12:n
cross multiply: 12(3) =6n, so n = 6
Answer:
(0.5455 ; 0.7545)
Step-by-step explanation:
Given that:
Sample size, n = 80
Baseball fans, x = 52
Proportion, p = x/n = 52 / 80 = 0.65
Using the relation :
Confidence interval :
p ± Zcrit√[(p(1 -p))/n]
Zcrit at 95% = 1.96
Lower boundary: p - Zcrit√[(p(1 -p))/n]
0.65 - 1.96√[(0.65(1 -0.65))/80]
0.65 - 1.96√[(0.65(0.35))/80]
0.65 - 1.96 * √0.00284375
0.65 - (1.96 * 0.0533268)
0.65 - 0.104520528
= 0.545479472
Upper boundary: p + Zcrit√[(p(1 -p))/n]
0.65 + 1.96√[(0.65(1 -0.65))/80]
0.65 + 1.96√[(0.65(0.35))/80]
0.65 + 1.96 * √0.00284375
0.65 + (1.96 * 0.0533268)
0.65 + 0.104520528
= 0.754520528
(0.5455 ; 0.7545)