CBSE Class 7 Mathematics Chapter 1 Integers NCERT Solutions

(a) By observing the number line, we can determine the temperature of each place:

• Bangalore: $22^\{\backslash circ\}C$
• Ooty: $14^\{\backslash circ\}C$
• Shimla: $5^\{\backslash circ\}C$
• Srinagar: $-2^\{\backslash circ\}C$
• Lahulspiti: $-8^\{\backslash circ\}C$

(b) To find the temperature difference between the hottest and coldest places:

• Hottest place temperature (Bangalore) = $22^\{\backslash circ\}C$
• Coldest place temperature (Lahulspiti) = $-8^\{\backslash circ\}C$
• Difference = Hottest Temperature - Coldest Temperature
• Difference = $22^\{\backslash circ\}C\; -\; (-8^\{\backslash circ\}C)\; =\; 22^\{\backslash circ\}C\; +\; 8^\{\backslash circ\}C\; =\; 30^\{\backslash circ\}C$

The temperature difference is $30^\{\backslash circ\}C$.

(c) To find the temperature difference between Lahulspiti and Srinagar:

• Temperature of Srinagar = $-2^\{\backslash circ\}C$
• Temperature of Lahulspiti = $-8^\{\backslash circ\}C$
• Difference = Temperature of Srinagar - Temperature of Lahulspiti
• Difference = $-2^\{\backslash circ\}C\; -\; (-8^\{\backslash circ\}C)\; =\; -2^\{\backslash circ\}C\; +\; 8^\{\backslash circ\}C\; =\; 6^\{\backslash circ\}C$

The temperature difference is $6^\{\backslash circ\}C$.

(d) To compare the combined temperature of Srinagar and Shimla with the temperature at Shimla and Srinagar individually:

• Temperature of Srinagar = $-2^\{\backslash circ\}C$
• Temperature of Shimla = $5^\{\backslash circ\}C$
• Combined temperature of Srinagar and Shimla = $-2^\{\backslash circ\}C\; +\; 5^\{\backslash circ\}C\; =\; 3^\{\backslash circ\}C$

Now, we compare:

• Is the combined temperature less than Shimla's temperature? . Yes, it is less than the temperature at Shimla.
• Is the combined temperature less than Srinagar's temperature? $3^\{\backslash circ\}C\; >\; -2^\{\backslash circ\}C$. No, it is not less than the temperature at Srinagar.

Jack's scores in the five successive rounds are given as 25, -5, -10, 15, and 10.

To find his total score, we need to add all these scores together:

Total Score = $25\; +\; (-5)\; +\; (-10)\; +\; 15\; +\; 10$

First, sum the positive numbers: $25\; +\; 15\; +\; 10\; =\; 50$

Next, sum the negative numbers: $-5\; +\; (-10)\; =\; -5\; -\; 10\; =\; -15$

Now, combine these sums: $50\; +\; (-15)\; =\; 50\; -\; 15\; =\; 35$

Therefore, Jack's total score at the end of the five rounds was 35 marks.

The temperature at Srinagar on Monday was $-5^\{\backslash circ\}C$.

On Tuesday, the temperature dropped by $2^\{\backslash circ\}C$. A drop in temperature means we subtract from the current temperature.

Temperature on Tuesday = Temperature on Monday - Drop in temperature

Temperature on Tuesday = $-5^\{\backslash circ\}C\; -\; 2^\{\backslash circ\}C\; =\; -7^\{\backslash circ\}C$

On Wednesday, the temperature rose by $4^\{\backslash circ\}C$ from Tuesday's temperature. A rise in temperature means we add to the current temperature.

Temperature on Wednesday = Temperature on Tuesday + Rise in temperature

Temperature on Wednesday = $-7^\{\backslash circ\}C\; +\; 4^\{\backslash circ\}C\; =\; -3^\{\backslash circ\}C$

Thus, the temperature on Tuesday was $-7^\{\backslash circ\}C$ and on Wednesday it was $-3^\{\backslash circ\}C$.

The height of the plane above the sea level is given as 5000 m.

The depth of the submarine below the sea level is given as 1200 m.

To find the vertical distance between the plane and the submarine, we need to add the distance of the plane above sea level and the distance of the submarine below sea level. This is because sea level is our reference point (0).

Vertical Distance = Height of Plane above sea level + Depth of Submarine below sea level

Vertical Distance = $5000\; \backslash text\{\; m\}\; +\; 1200\; \backslash text\{\; m\}$

Vertical Distance = $6200\; \backslash text\{\; m\}$

Therefore, the vertical distance between the plane and the submarine is 6200 m.