Maria = x
Tom = y
Use substitution
x+y=30
2y=x
2y+y=30
3y=30
y=10
Tom is 10 years old.
x+y=30
x+10=30
x=20
Maria is 20 years old.
answer: Rolling Two Dice. Note that there are 36 possibilities for (a,b). This total number of possibilities can be obtained from the multiplication principle: there are 6 possibilities for a, and for each outcome for a, there are 6 possibilities for b. So, the total number of joint outcomes (a,b) is 6 times 6 which is 36.
Step-by-step explanation: hopefully this is right
What is the MA of a 1st class lever?It can be any number > 0.What is the MA of a 2nd class lever?Always > 1What is the MA of a 3rd class lever?Always < 1 (it has to be > 0)A 58-tooth gear turns five times. It is connected to a 16-tooth gear. How many times does the 16-tooth gear turn?<span>TONO = TINI
TO = TINI ÷ NO
= 5 turns . 58 teeth ÷ 16 teeth
= 18.13 turns</span>A ramp with a mechanical advantage of 6.75 lifts objects to a height of 2.45 meters. How long is the ramp?<span>L = MAxH
= 6.75 . 2.45 m
= 16.54 m</span>A 65-tooth output gear is connected to a 24-tooth input gear. What is the MA of this system? Is force or speed multiplied?<span>MA = No ÷ Ni
= 65 teeth ÷ 24 teeth
= 2.71
Force is multiplied since MA > 1</span>A ramp that is 13.2 meters long is used to lift a 755 newton box up to a height of 1.11 meters. What is the MA of the ramp?<span>MA = L ÷ H
= 13.2 m ÷ 1.11 m
= 11.89</span>A lever can lift a 358 newton rock with a force of 93 newtons. If the length of the output arm is 1.45 meters, what is the length of the input arm?<span>MA = OF ÷ IF
= 358 N ÷ 93 N
= 3.85
IA = MAxOA
= 3.85 . 1.45 m
= 5.58 m</span>List the 7 types of simple machinesLever, pulley, wheel & axle, screw, wedge, ramp, gearDraw a pulley system with an MA of 3Look at the middle pictureDraw 2 different ramps. Mark the one with a greater MA with a star. How do you know it has the greatest MA?A has the greatest mechanical advantage since it is the most gently sloped. The steeper it is, the more force you have to apply, and the less MA it has.A machine is required to produce an output force of 1,357 newtons. If the machine has a mechanical advantage of 5.5, what input force must be applied to the machine?<span>IF = OF ÷ MA
= 1,357 N ÷ 5.5
= 246.73 N</span>What is the mechanical advantage of a wheel if the radius of the wheel is 34.95 cm and the radius of the axle is 8.2 cm?<span>MA = WR ÷ AR
= 34.95 cm ÷ 8.2 cm
= 4.26</span>What does MA tell you?MA tells you how much your input force is multiplied. It tells you how "easy" your task is. Remember you must trade less force for greater distanceWhich is greater, work output or work input? Why?Work input is greater due to FRICTION!An output gear turns 15 times. How many times will the input gear turn if the gear ratio is 30?<span>Ti = To ÷ GR
= 15 turns ÷ 30
= 0.50 turns</span><span>
</span>
Answer:
42
Step-by-step explanation:
