5 - 1.25 = 3.75
Melody’s mom pays her sister $3.75 for emptying the dishwasher.
Since Irina can paint 1 room in 9 hours, that means she paints 1/9 of the room in 1 hour. Her portion of the equation would be 1/9x, with x being the number of hours she works and 1/9 of a room per hour being her speed.
Since Paulo can paint 1 room in 8 hours, that means he paints 1/8 of the room in 1 hour. His portion of the equation would be 1/8x, with x being the number of hours he works and 1/8 of a room per hour being his speed.
The equation would then be 1/9x + 1/8x = 1 (Irina's portion of the room, plus Paulo's portion of the room, equal to one whole room).
Find a common denominator. 72 is the first number that both 9 and 8 divide evenly into. Since 9*8 = 72, we multiply the top of 1/9 by 8 to convert the fraction and get 8/72x. Since 8*9 = 72, we multiply the top of 1/8 by 9 to convert the fractio and get 9/72x. We now have 8/72x+9/72x=1
17/72x=1
Divide both sides by 17/72:
17/72x ÷ 17/72 = 1÷17/72
x=1/1 ÷ 17/72
x=1/1 * 72/17
x=72/17=4.24
Together it should take them 4.24 hours.
The formula for the triangular sequence is Xn=n(n+1)/2
So X25=25(25+1)/2=325
Answer:
your answer is 16
Step-by-step explanation:
Answer:
-17y+16x
Step-by-step explanation:
-3(3y -2x) +2(5x-4y)
Distribute
-9y +6x +10x -8y
Combine like terms
-9y -8y+ 6x+10x
-17y+16x
