Bissoy.com
Doctors Medicines MCQs Q&A

The average rainfall of January, February, and March was 280 mm. The average rainfall of February, March, and April was 282 mm. If the rainfall in April was 284 mm, what was the rainfall in January?

The average rainfall of January, February, and March was 280 mm. The average rainfall of February, March, and April was 282 mm. If the rainfall in April was 284 mm, what was the rainfall in January? Correct Answer 278

Given∶

The average rainfall of January, February, and March was 280 mm.

The average rainfall of February, March, and April was 282 mm.

The rainfall in April was 284 mm.

Formula Used∶

Sum of observations = Average × No. of observations.

Calculation∶

Sum of rainfall on Jan, Feb and March = 280 × 3 = 840 mm   ----(1)

Sum of rainfall on Feb, March and April = 282 × 3 = 846 mm   ----(2)

Rainfall in April = 284 mm   ----(3)

∴ The rainfall on January = (840 + 284 – 846) mm = 278 mm

∴ The rainfall in January was 278 mm

Related Questions

The rainfall in Shillong for the first two days was in the ratio of 6 : 7. The average rainfall for the last four days was recorded to be 0.90 inch. The average rainfall of six days was 1.25 inch. Which of the following is/are correct? A. Average rainfall on 2nd day is 2.8 inch B. Average rainfall on 1st day is 1.8 inch C. Average rainfall on 2nd day is 2.1 inch D. Average rainfall on 1st day is 2.4 inch
The monthly rainfall chart based on 50 years of rainfall in Agra is shown in the following figure. Which of the following are true? (k percentile is the value such that k percent of the data fall below that value) (i) On average, it rains more in July than in December (ii) Every year, the amount of rainfall in August is more than that in January (iii) July rainfall can be estimated with better confidence than February rainfall (iv) In August, there is at least 500 mm of rainfall
Raw material purchased:
1st January, 600 units @ Rs. 12 per unit
12th January, 500 units @ Rs. 14 per unit
21st January, 300 units @ Rs. 13 per unit
Raw material issued for manufacture:
3rd January 300 units
5th January 124 units
15th January 250 units
16th January 300 units
Raw material returned to stores from manufacturing department on 14th January, 50 units. The material is issued on First-in-First out method.
The value of material remaining in store on 21st January will be:
The following bar graph shows the quantity of paddy sold in the month of January, February, March and April. If the difference between quantities of paddy sold in February and April is 6 quintals, then what is the total quantity of paddy sold in January and March in quintal?
Consider the following statements: 1. The normal annual rainfall of a station is obtained as the arithmetic average of the successive annual rainfall in the last 30 years. 2. The “normal rainfalls” are updated by deleting the needful number of oldest years’ data from the record and adding the needful number of most recent years’ data to the record. 3. The standard deviation computed for the rainfall data is taken as a measure of the variability of the rainfall during the self-same set of years. 4. If the observed rainfall in any year is less than the current average annual rainfall, then that year is called a dry year. Which of the above statements are correct?
Venkatesh's average salary for the month of January, March, and April is 50000 and average salary for the month of January, March and May is Rs 40000, then how much difference in the salary of Venkatesh for the month of April and May. 
In the question below are given four statements followed by two conclusions numbered I and II. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the given statements disregarding commonly known facts. Statements: All Woman are Man. Some Woman are March. All March are April. No March is Sunday. Conclusions: I. Some Woman are April. II. Some March are Man. III. Some April are Sunday
The following table shows the Air Quality Index (AQT) (PM2.5) for the four weeks of February 2018. What is the difference in the average of AQI in Kolkata and Delhi in the month of February? Toxic Trend Air Quality Index Period Kolkata Delhi February 1st – 7th 306 248 February 8th – 14th 288 246 February 15th – 21st 274 246 February 22nd – 28th 172 236
The average salary of a person for the months of february, march, april and may is Rs.12000. For the months of march, april, may and june is Rs.3000. If his salary for the month of June is Rs.3000 then what is his salary for the month of february ?
The average salary of a person for the months of February, March, April, and May is Rs. 12,000, and that for the month's March, April, May June is Rs. 13,000. If his salary for the month of June is Rs. 8,000, then what is his salary for the month of February?