You can change all of these to decimals and then solve or get common denominators.
8.75 + n + 2.375 + 4.5 = 23.125
15.625 + n = 23.125
Subtract 15.625 from both sides
n = 7.5
Answer:
Astronomers were trying to find the weight of six planets - Mars, Venus, Pluto, Jupiter, Mercury, and Saturn. The number of planets lighter than Mars was equal to the number of planets heavier than Venus. Saturn was heavier than Mars and Mercury were heavier than Pluto. Venus was lighter than Mars. Saturn was not the heaviest planet.
Step-by-step explanation:
115>5.75x+28.75
5.75x+28.75<115
5.75x<115-28.75
5.75x<86.25
x<86.25/5.75
x<15 or (-∞,15)
Answer: x<15 or (-∞,15)
Answer:
z<8
Step-by-step explanation:
First: write down the equation : 6z<48
Second: divide both sides with 6 (since its the only number that can be divided for both sides)
Third: then you'll get z<8
Let Daniel's age be 'x' years , hence, Lisa's age is (x - 5) years. Let Grandma's age be 'y' = 54 years.
Hence,
x(x - 5) = 2/3 × y
x² - 5x = 2 × 54 years / 3
x² - 5x = 36 years
x² - 5x - 36 = 0
∆ = (-5)² - 4(1)(-36) = 25 + 144 = 169
√∆ = √169 = 13

x1 = (5+13)/2, x2 = (5-13)/2
x1 = 9, x2 = -4
Since, age can't be negative,
Daniel's age = x = 9 years.