Arithmetic problems for Grade 5

10 problems with worked solutions.

№ 1 · Arithmetic · Grade 5

Find the sum of numbers from 1 to 30 that are not divisible by 3.

№ 2 · Arithmetic · Grade 5

Two warning lights flash every 12 and 18 seconds. Now they blinked simultaneously. In how many seconds will this happen again for the first time?

№ 3 · Arithmetic · Grade 5

Solve the equation: three times an unknown number plus 17 equals 68. What is the unknown number?

№ 4 · Arithmetic · Grade 5

The book has 240 pages. On the first day, they read a third of the book, and on the second, a quarter of the remaining pages. How many pages are left after two days?

№ 5 · Arithmetic · Grade 5

One craftsperson can complete an order in 6 hours, and another can complete it in 3 hours. How many hours will they need to complete the same order if they work together at constant rates?

№ 6 · Arithmetic · Grade 5

How many different natural factors does the number 360 have, including 1 and the number 360 itself?

№ 7 · Arithmetic · Grade 5

In a group, the ratio of boys to girls is 3:5. There are 32 children altogether. How many are girls?

№ 8 · Arithmetic · Grade 5

A warehouse has 640 parts. Inspectors selected 12.5 percent of them. How many parts were selected?

№ 9 · Arithmetic · Grade 5

The number 500 was increased by 20 percent, and then the result was decreased by 20 percent. What number was obtained?

№ 10 · Arithmetic · Grade 5

One robot assembles 18 parts per hour and another assembles 12 per hour. How many parts will they assemble together in 4 hours?