1 car - 4 wheels
1 motorcycle - 2 wheels
x - number of cars
y - number of motorcycles
so, there are 70 vehicles: x + y = 70
and all togeather they've got 258 wheels: 4*x + 2*y = 258
because each car has 4 wheels, so all car wheels = 4*x,
likewise 2*y for motorcycles
x + y = 70 /* 4
4 x + 2y = 258
4 x + 4 y = 280 (R1)
4 x + 2y = 258 (R2)
2y = 22 /:2 it is R1 - R2
x = 70 - y
y = 11 /motorcycles
x = 70 - 11 = 59 /cars
check:
59 + 11 = 70 ok
59 * 4 + 11 * 2 = 236 + 22 = 258 ok
To solve this problem, we are going to use a scientific/mathematics strategy called Dimensional Analysis.
40 miles / 1 hour * 5280 feet / 1 mile = 211200 feet / 1 hour
211200 feet / 1 hour * 1 hour / 60 minutes = 3520 feet/ 1 minute
3520 feet / 1 minute * 1 minute / 60 seconds = approximately 59 feet / 1 second
Jackrabbits travel approximately 59 feet per second, when rounded to the nearest whole number.
In a full rotation, 360°, a point on the edge of a gear would travel a distance equal to its circumference. The circumference of a circle is:
C=2πr, and since we are only traveling 150°, we need to set up an appropriate ratio for circumference to the distance the point travels:
d/C=150/360
d=5C/12 and since C=2πr
d=10πr/12
d=5πr/12, and since r=4in
d=5*4π/12 in
d=20π/12 in
d=5π/3 in
d≈5.24 in (to nearest hundredth of an inch)
425 is decreased to 319.
The above statement means that a number should be deducted from 425 to get the difference of 319.
Let x be the unknown number.
425 - x = 319
425 - 319 = x
106 = x
106 is the unknown number.
It can be phrased like this: 425 decreased by 106 is 319.
Answer:
Equilateral triangle
Step-by-step explanation:
Equalateral triangles has 3 60 degre angles, and 3 congruent sides
