How do I solve this problem?
Distance = Rate X Time There are two parts of the equation. One is going there and the second is coming back. However, the distance of each is the same, so set them equa to each other to solve once you identify the Rate and Time for each. It is important to recognize that since the total time is 4.5 hours, it must be represented as two separate parts T and 4.5 - T. Here is the equation to be used (remember D = RT and both D's are equal so, RT = RT): 5(4.5 - T) = 40T 22.5 - 5T = 40T 22.5 = 45T 1/2 = T Since the distance is 40T (or you can use 5(4.5 - T)), substitute 1/2 for T and you will get 40 times 1/2 which equals 20. The answer is 20 km.
How do I solve this problem?
Well it depends if you can get the same dessert as a combo. In that case, you can choose any of the 8 and then you can choose any of the 8 again. Therefore 8*8 = 64 combinations. If you are not allowed to choose the same dessert, then it would be 8 possibilities for your first choice, and 7 for your second choice. Therefore 8*7 = 56 combinations
How do i solve this problem?
For isosceles triangle; the two legs are equal; so Perimeter of Isosceles = 2 Leg + Base Let L = Length of each leg then 2L + 85 = 345 cm. ==> 2L = 345 - 85 cm. ==> 2L = 260 cm. ==> L = 260/2 cm. ==> L = 130 cm. Answer: The length of each leg is 130 cm.
How do i solve this problem?
A stone is tied to a string (length = 0.600 m) and whirled in a circle at the same constant speed in two different ways. First, the circle is horizontal and the string is nearly parallel to the ground. Next, the circle is vertical. In the vertical case the maximum tension in the string is 14.0% larger than the tension that exists when the circle is horizontal. Determine the speed of the stone.
How do i solve this problem?
PART 1: The wheel is 15 inches. The circumference is: 2πr = 2 π (15) = 30 π ≈ 94.25 inches But it makes 3 revolutions in a second, so that is: 3 x 94.25 ≈ 282.75 inches / second. PART 2: Now to express that in miles per hour. If you go 282.75 inches in a second, you will go 60 times that in a minute, or 3600 times that in an hour. 282.75 x 60 x 60 = 1,017,876 inches / hour But we want this in miles: 5280 feet x 12 inches/ft = 63,360 inches in a mile. Now just divide: 1,017,876 / 63,360 ≈ 16.064 mph
How do i solve this problem?
Forget the Billion for a minute 15.4 l has 1.9 x10^-5 M H2SO4 (RFM = 98) has 29.3 x 10^-5 mol 15.4 l has 8.7 x 10^-6 HNO3 (RFM = 63) has 13.4 x 10^- 5 mol Total number of H3O+ = 29.3 x2 + 13.4 = 72 x 10 ^-5 mol assuming Limestone is 100% CaCO3 CO3= + 2H3O+ ===> CO2 + 2H2O So 36 x 10^-5 mo, CaCO3 required = 100 x 36x10^-5 g = 0.036g Now scale up to lake size 1 billion kg has 1 x 10^12 g times by 0.036g = 36 million kg is your answer 36 000 metric tons or 1000 v large trucks
How do i solve this problem?
Calculate the mechanical advantage of a group of pulleys used to raise an engine from a car. The engine is raised 1.2m with the pulleys when 4.8m of rope is pulled through the pulleys.
If you could solve any one world problem, what would it be?
Global Warming.If we leave the global warming to continue on the path its currently moving there are going to be major crisis in about 30 - 40 years. Crisis of proportion we haven’t seen that will lead to wars between the nations over resources especially water.One exampleOver half billion people depend on river Ganga which is fed through glacier in Himalayas. This glacier is retrieving at an alarming rate due to warming temperatures. If this continuous the glacier can disappear in the next 30 years making river Ganga a seasonal river which means the river will dry up during summer and other times. Imagine half a billion people without water for crops, cattle, human consumption. That will lead to unrest that we haven’t seen, pushing people to migrate only to find such problems everywhere. Its an extremely scary situation!!
How should I go about solving problems at SPOJ?
SPOJ has A LOT of problems. Clearly, one can't expect to solve all of them. Besides there are many problems that are just too easy (still not moved to tutorials section) or are complete repetition of another problem with a different story.If you are just starting:You can follow a top ranker's submission (any one in top 300-400 should do). But there are many great users who only solve hard problems and earned a lot of points doing so, following one of them is not advised if you are just starting. Try someone who has solved atleast some easy problems in the beginning and then eventually moved to tougher problems.You can select topics one by one, and start solving problems related to it. This way you can taste all flavors of programming paradigms and would solve atleast some problems in each of them. If done right, you will be confident enough to select a problem randomly and start solving it.If you already have some experience with programming:Just randomly choose a problem, see if it is hard enough, you can guess its hardness by when it was added to SPOJ and how many people have solved it. You can follow my submissions if you want to or choose someone more experienced than me. http://www.spoj.com/users/pankajj/Or if you want to learn by selecting topics one by one and solving some problems, you can try thisLeague of Programmers