Quiz Discussion

Out of the total production of iron from hematite, an ore of Iron, 20% of the ore gets wasted, and out of the remaining iron, only 25% is pure iron. If the pure iron obtained in a year from a mine of hematite was 80,000 kg, then the quantity of hematite mined from that mine in the year is

• 1] 5,00,000 kg
• 2] 4,00,000 kg
• 3] 4,50,000 kg
• 4] None of these

In the recent, climate conference in New York, out of 700 men, 500 women, 800 children present inside the building premises, 20% of the men, 40% of the women and 10% of the children were Indians. Find the percentage of people who were not Indian?

• 1] 77%
• 2] 73%
• 3] 79%
• 4] 83%

The price of raw materials has gone up by 15%, labor cost has also increased from 25% of the cost of raw material to 30% of the cost of raw material. By how much percentage should there be reduction in the usage of raw materials so as to keep the cost same?

• 1] 28%
• 2] 17%
• 3] 27%
• 4] 24%
• 5] Cannot determined

The actual area of a rectangle is 60 Cm2, but while measuring its length a student decreases it by 20% and the breadth increases by 25%. The percentage error in area, calculated by the student is :

• 1] 5%
• 2] 15%
• 3] 20%
• 4] No change

The shopkeeper increased the price of a product by 25% so that customer finds difficult to purchase the required amount. But Somehow the customer managed to purchase only 70% of the required amount. What is the net difference in the expenditure on that product ?

• 1] 55 more
• 2] 10% more
• 3] 12.5% less
• 4] 17.5% less
• 5] None of these

The square of a positive number is 2000% greater than the number itself, then the square of that number is :

• 1] 1762
• 2] 1635
• 3] 441
• 4] 139

30% of a number when subtracted from 91, gives the number itself. Find the number.

• 1] 60
• 2] 65
• 3] 75
• 4] 70
• 5] None of these

A number x is mistakenly divided by 10 instead of being multiplied by 10. what is the percentage error in the result?

• 1] -99%
• 2] -100%
• 3] +99%
• 4] +100%

Connie has a number of gold bars, all of different weights. She gives the 24 lightest bars, which weigh 45% of the total weight, to Brennan. She gives the 13 heaviest bars, which weigh 26% of the total weight, to Maya. She gives the rest of the bars to Blair. How many bars did Blair receive?

• 1] 14
• 2] 15
• 3] 16
• 4] 17
• 5] 18

The cost of packaging of the mangoes is 40% the cost of fresh mangoes themselves. The cost of mangoes increased by 30% but the cost of packaging decreased by 50%, then the percentage change of the cost of packed mangoes, if the cost of packed mangoes is equal to the sum of the cost of fresh mangoes and cost of packaging :

• 1] 14.17%
• 2] 7.14%
• 3] 8.87%
• 4] 6.66%