Prime numbers - 7th grade (12y) - math problems

Number of problems found: 136

  • Prime factors
    prime Factor the number 6600 into the product of prime numbers.
  • Decomposition
    prime_factorization Make decomposition using prime numbers of number 155. Result write as prime factors (all, even multiple)
  • Prime factors
    prime Write 98 as product of prime factors
  • Prime divisors
    plusminus_1 Find 2/3 of the ratio of the sum and the product of all prime divisors of the number 120.
  • Raffle
    tombola_tickets In the pool is numbers from 1 to 115. What is the probability that a randomly selected number is not a prime number?
  • Common divisors
    prime Find all common divisors of numbers 30 and 45.
  • Lcm of three numbers
    prime What is the Lcm of 120 15 and 5
  • Twenty-five
    prime How many three-digit natural numbers are divisible by 25?
  • Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  • Divisible by nine
    numbers_2 How many three-digit natural numbers in total are divisible without a remainder by the number 9?
  • Rectangles
    rectangles How many rectangles with area 8713 cm2 whose sides are natural numbers are?
  • Summands
    magic Find two summands of the number 42, so that its product is minimized.
  • No. of divisors
    triangle_div How many different divisors have number ??
  • LCM
    calc_icon What is the least common multiple of 5, 50, 14?
  • Number
    prime What number should be placed instead of the asterisk in number 702*8 to get a number divisible by 6?
  • Four-digit number
    numbers_1 Find also a four-digit number, which quadrupled written backwards is the same number.
  • Lcm simple
    lcm_gears Find least common multiple of this two numbers: 140 175.
  • Counting number
    numbers2_49 What is the smallest counting number divisible by 2,5,7,8 and 15?
  • Flowerbeds
    meter_24 What is the smallest length of flowerbeds we have to prepare to plant seedlings at grid 20,30,25,40 cm?
  • Plums
    svestka In the bowl are plums. How many would be there if we can divide it equally among 8, 10 and 11 children?

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Prime numbers - math word problems. Examples for 7th grade (seventh).