Answer:
P(draw a blue or red marble) = ![\frac{16}{21}](https://tex.z-dn.net/?f=%5Cfrac%7B16%7D%7B21%7D)
Step-by-step explanation:
The bag contains 8 blue, 5 green, and 8 red marbles
Total number of marbles is 8 + 5 + 8 = 21
P(draw a blue or red marble) = P(blue marble) or P(red marble)
In probability,"Or" means addition (+)
So, P(draw a blue or red marble) = P(blue marble) + P(red marble)
P(draw a blue or red marble) =
+
= ![\frac{16}{21}](https://tex.z-dn.net/?f=%5Cfrac%7B16%7D%7B21%7D)
P(draw a blue or red marble) = ![\frac{16}{21}](https://tex.z-dn.net/?f=%5Cfrac%7B16%7D%7B21%7D)
Let's solve your equation step-by-step.
0.3(n−5)=0.4−0.2(n−7)
Step 1: Simplify both sides of the equation.
0.3(n−5)=0.4−0.2(n−7)
(0.3)(n)+(0.3)(−5)=0.4+(−0.2)(n)+(−0.2)(−7)(Distribute)
0.3n+−1.5=0.4+−0.2n+1.4
0.3n−1.5=(−0.2n)+(0.4+1.4)(Combine Like Terms)
0.3n−1.5=−0.2n+1.8
0.3n−1.5=−0.2n+1.8
Step 2: Add 0.2n to both sides.
0.3n−1.5+0.2n=−0.2n+1.8+0.2n
0.5n−1.5=1.8
Step 3: Add 1.5 to both sides.
0.5n−1.5+1.5=1.8+1.5
0.5n=3.3
Step 4: Divide both sides by 0.5.
0.5n0.5=3.30.5
n=6.6
Step-by-step explanation:
1a)you are asked to find the number of girls and boys who received prizes
1b)The given facts are that out of 60 pupils, 40 being boys, 20 being girls, joined a Math Quiz competition. 20%of boys and 15 of girls received prizes.
1c)40 boys +20 girls=60 pupils.
1d) Find the number of girls and boys that re ceived prizes
20% of 40 boys
20/100 ×40= 8 boys won prizes
15% of 20 girls
15/100×20=3 girls won prizes
1d) 8 boys+3 girls=11 pupils won prizes