For 1. To estimate how many sports cards Alberto had, you would round each number to the nearest ten, so 318 would become 320. 273 would then become 270. You would then add those two and would get 590. So, Alberto had 590 sports cards (estimated). If you were looking for the actual answer (not estimated) , you would get 591.
If you had a fair coin, the probability of seeing heads is 1/2, meaning you’d see heads 30 times
Answer:
1. 5/3 cm
2. 10 in
Step-by-step explanation:
1. The length of a rectangle is 4 cm more than 3 times its width.
Let the length be L and the width B
Then,
L = 4 + 3B
If the area of the rectangle is 15 cm2
Area = LB = 15
B(4 +3B) = 15
3B² + 4B - 15 = 0
3B² - 5B + 9B - 15 = 0
B(3B - 5) + 3(3B - 5) = 0
(3B - 5)(B + 3) = 0
3B - 5 = or B + 3 = 0
B = 5/3 or -3
since B cannot be negative, B = 5/3 cm
2. The ratio of length to width in a rectangle is 2 ∶ 3.
Let the length be L and the width B
Then,
L/B = 2/3
2B = 3L, B = (3/2)L
when the area is 150 in2.
Area = LB = 150
(3/2)L² = 150
L² = 150×2÷3
L² = 100
L = √100
L = ±10
since the length cannot be negative, L = 10 in
If x is the number of tickets she has left, then 2x is the number she has used (2×number of rides she has gone on). So the number she has left would be...
14 - 2x
We can now find an equivalent expression by replacing the x with a number... for example...
14 - 2(2)
This would be if she rode two rides. You could solve the equation like this...
14 - 2x =
14 - 2(2) =
14 - 4 = 10
After 2 rides she has 10 tickets left.
