Question
The Element/Ion which is essential in small quantities
for the development of healthy teeth but causes mottling of the teeth if consumed in higher quantities isSolution
Fluoride in small quantity protects the teeth but in high quantity it causes fluorosis which deforms the teeth.
A boat can travel 45 km downstream in 50 min. The ratio of the speed of the boat in still water to the speed of the stream is 5: 4. How much time will t...
The speed of a boat in still water is 30 km/hr. If the boat covers 160 km in upstream in 8 hours, then find the time taken by the boat to travel 120 km ...
Find the total distance covered by boat in each upstream and downstream in 4 hours if the speed of boat in still water and speed of current is 15 km/h a...
Speed of boat in still water is 60% more than speed of current and total time takes by boat to cover certain distance going downstream and upstream is ...
A boat running downstream covers a distance of 55 km in 5 hrs and covering the same distance upstream in 11 hrs. What is the speed of a boat in still wa...
A boatman covers 192 km upstream in 4 hours and 288 km downstream in 4 hours. Find the time taken by the boatman to cover 240 km in still water.
The speed of the boat in still water is 12 km/hr and the speed of the stream is 9 km/hr. A boat goes 105 km downstream with its usual speed but at the t...
Speed of boat is 20 km/hr. Speed of the stream is 20% less than speed of boat. Then find time taken by boat to go 72 km downstream?
A boat takes a total of 1.5 hours to cover 20km upstream and 15 km downstream. If the boat takes 4.8 hours to cover 120 km in still water, then find the...
A boat can cover 195 km in downstream in 10 hours and 140 km in upstream in 14 hours. Find the distance travelled by the boat in still water in 4 hours.
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